"Good informant, good case. Bad informant, bad case. No informant, no case."
(Police saying)

    The ability to be resourceful at information gathering and collection is the key determinant of success at policing and with criminal investigation.  When police are lacking witnesses (which is often the case), especially eyewitnesses, dealing with sophisticated criminals, or not getting much out of the crime scene evidence, they turn to tried and true methods of law enforcement -- informants and surveillance.  Other sources of information also exist that are either public or private, open or confidential, and the Internet, of course, has become a tremendous reservoir of open source information.  Use of informants is the more legally permissive, yet ethically repugnant activity; and use of surveillance is the more legally regulated, yet ethically sound activity.  That's because informants are often used in the loose, early phases of an investigation to develop leads, and the activity of managing informants almost always involves compromising the integrity of law enforcement.  Surveillance, on the other hand, is a well-established craft involving technique and gadgets, and is almost always used to seal the fate of a target who has most likely already provided the police with enough facts to establish probable cause.  At least that's my opinion, but there are those (Marx 1988) who think surveillance is the greater evil, and there are those (Madinger 2000) who think informants are just another way ethical citizens can get involved in law enforcement.

    It's important to note at the outset that use of informants and surveillance should be methods of last resort.  These are not methods for screening-out, or eliminating potential suspects from further consideration; quite the opposite, they "screen-in" or incriminate more suspects than usual (Gill 2000).  These are methods that are expensive, time-consuming, and controversial.  They are inherently stressful and dangerous, and undercover work is risky.  Any and all information obtained from such sources, including open sources, should be regarded as untrustworthy until it is corroborated by other sources and/or converted from information into intelligence.  The word intelligence usually means information that has been subjected to analysis and synthesis.  It also usually means that the same information is coming from different sources and has been checked out, or tested, as reliable. 


    A cultivated source (as opposed to a regular source) is neither a victim, witness, or suspect in an investigation involving them or against them, but is someone with connections to the criminal underworld that is able to tell you things that are about to happen.  Cultivated sources make the best informants.  Apprehended criminals who turn informants (or "flip" as its called) in hope of having their charges dropped or reduced have NOT been cultivated.  Their value is worthless because evidence law sees them as saying or doing something out of self-interest.  At law, there is a presumption of truth in anything someone says or does against their self-interest or safety, not in their self-interest if criminal charges are pending against them.  Ideally, you want active informants reporting information about future crime, not witness informants for past crimes.  Likewise, jailhouse informants (or "snitches")

    Cultivated sources typically include people doing business around an area where criminals conduct their business.  Examples include taxi drivers, hotel employees, airline employees, automobile salespeople, doormen, gun dealers, bartenders, private investigators, apartment managers, package delivery employees, and proprietors or employees of restaurants.  The idea is that such people can get as close to criminal suspects as possible (as, for example, their regular barber or prostitute) without getting so close you're treading on privileged relationships (as, for example, their wife or psychotherapist).  It should be obvious by now that these types of informants constitute a deviant street network of eyes and ears for the police.  By using such sources, you are looking for signs of crime in the making.  You are NOT doing infiltration or undercover work.  If anything, you are doing the equivalent of espionage work by setting up a ring of spies, or agents-in-place.  All you have to do in managing such people is keep them from doing or provoking criminal things, but also keep them close to their own sources of knowledge about criminal happenings which you conveniently check out for corroboration purposes.  

    It used to be common for each and every police officer to have their own set of informants or deviant street connections (as described above).  Today, most police departments only allow (and encourage) their detectives to cultivate informants, but there are inconsistencies in how they are registered and handled.  Federal agencies have always held to the practice of registering informants to the agency (almost as quasi-employees), but municipal agencies tend to register (when they do register or record the informant) to the individual detective.  This creates the problem of lost informants (nobody contacts them anymore) when a municipal detective retires or leaves.  There is also the problem of how to disseminate the informant registry within the police department (the Chief usually keeps it secret) because you don't want other officers arresting or messing with your informants.  

    When an informant is on the payroll, they are usually registered because the law requires financial auditing.  They are also most likely to hold the status of confidential informant, although this term technically refers to informants who have some special knowledge about a past or future crime and are potential targets for violence and revenge.  Confidential informants, or CIs, are allowed to be referred to as anonymous or unnamed affiants in affidavits, do not appear on any other legal documents, and never have to be disclosed in court or via any discovery process.

    The management of informants is mostly a matter of knowing what motivates them, and always making sure this motivation continues to have some currency.  There are many motivation-based typologies of informants in the literature.  Osterburg & Ward (2000) present one that distinguishes the following:

    Another useful typology is presented by Weston & Lushbaugh (2003) who distinguish the usefulness of the informant as well as the quality of their information:

    Finally, there is the oldest typology of motives which has been around for some 40 years simply because they never change (Harney & Cross 1960):

    Proper handling of informants requires reward and control (Hight 2000).  There should be some system of departmental awards or rewards, but at the same time, criminal and deviant activity should not be condoned.  Disastrous consequences can result from becoming too informal, too unprofessional, or too involved in relationships with informants.  The keys to success at working an informant, according to Madinger (2000) are MOTIVATION + ACCESS + CONTROL.  You only have a good informant if all three of these are present.  The most precious asset you have in working an informant is trust.  An informant must trust that you will always be true to your word, and that everyone all the up from the lowest ranking police officer to the chief prosecutor will keep their identity secret.


    The United States was the first country to establish witness protection programs, and they started in 1971 (with the Organized Crime Act of 1970) and were modified by the Comprehensive Crime Control Act of 1984 to cover some relatives and associates of the witnesses.  The law gives the Department of Justice freedom to arrange for the security of witnesses as they see fit, but there are tough standards for getting in.  First, the testimony has to be essential to the case, and there must be clear evidence that the witness' life or his/her family's life is in danger.  If testimony is available from someone at less risk, then that person should (and is) used.  Those who are most successfully admitted into witness protection are also the most credible and reliable witnesses.  It is very clear what they will say, and that they are going to show up at trial.  Anyone who flip-flops on the stand doesn't get any new identity.  The U.S. Attorney General's office has the final say in who gets admitted into the program,

    The new identity is chosen by the witness and his/her family.  Care should be exercised to not choose a name that is similar to the old name or one that a family researcher might come up with.  The U.S. Marshals Service then tries to find a reasonable job opportunity (cover) for the witness.  In some cases, the government pays for vocational training.  The government also assists (but does not pay for) housing.  Witnesses normally receive about $60,000 in subsistence payments, but if they are unemployed and not actively seeking employment, the payments stop.  No payments or privileges (other than the protected identity) go out to family members of the witness (although rare circumstances may dictate that happening occasionally).  No contact is allowed with unprotected family members (or past associates).  Protected witnesses are also prohibited from ever returning to or visiting any city they lived in before.  In the case of a protected witness returning to the ways of crime (and there's some chance of that), the witness' true identity is usually shared with local law enforcement, but there's no automatic or continuing immunity.  What usually happens is that a re-offending protected witness is sent back to prison (under a new identity) and placed under protective custody by corrections officials.  If a protected witness commits a crime, then the victims of that crime receive compensation out of a Victim Compensation Fund.

    Numbers of protected witnesses is classified.  Since the U.S. started using witness protection, no protected witness has been killed yet.  The model has been successfully imported to other countries, and has extended from organized crime cases to gang crime, drug trafficking, and terrorism cases.  Australia, Germany, Colombia, and even China have witness protection programs.  The International Criminal Court also has a witness protection program for use in crimes against humanity cases.    


    There are legal restrictions on how far law enforcement can go in keeping an informant's identity a secret.  The general rule is that confidentiality (as in "confidential informant" or "affiant") can be maintained if the informant was used in the early stages of a case, say the reasonable suspicion stage, not the probable cause stage, and most definitely if the informant is not required to be a witness at trial.  In some situations, however, the Jencks Act or court decisions involving Brady v. Maryland may be invoked, forcing the prosecutor to at least turn over a transcript of statements made by the informant.  The extreme situation would require a judge to agree that exculpatory information might be found by revealing the informant's identity (an unlikely scenario).  Most prosecutors, however, would drop the case or reduce the charges in honor of a police promise to maintain confidentiality.  

    Courts have always recognized police use of informants a historical tradition with no inherent moral weakness (U.S. v. Dennis 1950).   Probably the most significant case in recent years was Hoffa v. U.S. (1966) in which the Court considered, among other things, whether a police informant must identify themselves as working with police under certain conditions such as when they are recruiting other informants.  After all, there is a precedent like this in espionage law.  The opinions in Hoffa and a subsequent case (Maine v. Moulton 1985) yielded a requirement that police admonish their informants to act natural and not try to draw out any particular incriminating statements that would constitute the functional equivalent of police questioning.  

    Courts will not tolerate the use of informants for entrapment.  Any incriminating statements made to an informant, in response to the informant's remarks, which prompted the statement, will be inadmissible.  Entrapment is defined as inducing a person to commit a crime they did not contemplate for the sole purpose of instituting a criminal prosecution against them.  Inducement is perceived by the Courts as persistent coercion or trickery.  Placing opportunity in front of the suspect is not normally entrapment, but repeatedly providing them with the same opportunity over and over again could be construed as persistent coercion.  Similarly, playing on a suspect's weaknesses such as their vanity or tendency to boast, could be construed as trickery if it was being constantly prompted by an informant.  Above all, you should avoid using what is called an "agent provocateur" who is a person who provokes or incites crime, such as someone who urges a mob to riot or urges someone armed and angry to shoot.

    Another thing to avoid is referring to your informants as "special employees" or employees of any sort.  This used to be fairly standard law enforcement practice up until the late 1960s and early 1970s, and at least one court case did involve a suit by such an informant demanding civil service benefits for years of service.  This kind of situation will most likely come up when you need an informant with special skills (such as foreign language proficiency or computer skills), or when an ex-informant puts previous law enforcement experience on their resume.  Modern law enforcement practice strongly discourages informants from thinking of themselves as employees.

    A final word of advice is NEVER meet with an informant alone.  Some have been known to kill their police handler, and others "set up" their handler for assault or robbery, make false claims about physical or sexual abuse, and allege that they were involved in a shakedown or extorted for money and/or drugs.  The initial debriefing (establishment of motive and/or registration) of an informant should always take place on the officer's turf, preferably in an office somewhere.  Later meetings with the informant can occur in a vehicle, safe house, or public place.  A regular schedule of telephone and face-to-face contacts will go a long way at convincing courts that this is a managed informant who follows directions and has some credibility.  So too, will corroboration establish credibility.  Police corroborate, or double-check, what the informant says in a number of ways:


    Surveillance is the clandestine collection and analysis of information about persons or organizations, or put another way, methods of watching or listening without being detected.  Most surveillance has physical and electronic aspects, and is preceded by reconnaissance, and not infrequently, by surreptitious entry (to plant a monitoring device).  Surveillance can be a valuable and essential tool in combating a wide range of sophisticated criminal activities, including such offenses as kidnapping, gambling, narcotics, prostitution, and terrorism.  There are many different types of surveillance.  Peterson and Zamir (2000), for example, list seventeen types: audio, infra/ultra-sound, sonar, radio, radar, infrared, visual, aerial, ultraviolent, x-ray, chemical and biological, biometrics, animals, genetic, magnetic, cryptologic, and computers.  A shorter list would include four general types of surveillance: visual; audio, moving, and contact.  Here is an outline of the four types from that shorter list:




IV. CONTACT (aka TRACERS, DYE STAINS--fluorescent stains)

    Preparation is key to a successful surveillance, regardless of type. Learn all you can about your subject and the neighborhoods in which you will be operating in.  Whenever possible, target information should be individualized, including who the associates are of your main target.  If at all possible, it is a good idea to make a thorough RECONNAISSANCE of the areas in which you plan to conduct the surveillance to try to spot any known criminals who are operating in the area. Familiarize yourself with the geography of the area. Learn the names and locations of streets, alleys and passage ways. Observe traffic conditions. Form a mental picture of where various buildings are located.

    Effective surveillance requires TEAMWORK. A clear chain of command must be established, and every officer must fully understand what is expected. Everyone involved should be briefed about the operation and any special hazards or problems should be anticipated. Knowledge of a surveillance operation in progress should be kept secret, but it is often useful to notify other authorities in the area so that suspicious person reports are avoided and two or more ongoing law enforcement operations do not bump into one another.  Some experts argue that it takes the resources of twelve operators and six vehicles to put one ordinary individual under effective 24-hour physical surveillance.

    Select the best OBSERVATION POST by studying a large scale map of the area, combined with your reconnaissance. The map will allow you to check the angles of view from different locations. When no adequate indoor observation post is available, set one up outdoors. Personnel may pose as repairmen, street vendors, or other such people who would not arouse suspicion. Sometimes cars and trucks can provide cover. Indoor posts, however, permit the most use of equipment, such as spotting scopes, cameras, and recording devices. All personnel at an observation post should have cover stories.

    MOVING SURVEILLANCE is complex and offers the chance of surprise. It makes heavy demands on resourcefulness. This is where blending into the environment is most important. Officers should carry extra items such as a hat, glasses, and a raincoat to permit changes of appearance. Remember to carry loose coins and small bills so you can pay exact fare rather than wait for change, and to carry pen and paper to leave a note when necessary. Sometimes, it will be necessary to develop a set of signals that can be used on the street without tipping off the suspect. Such things as how a newspaper is carried or the way clothing is worn works well for this.

    On FOOT, a suspect can easily shake off a single follower without too much trouble. If you must follow a subject alone, it is best to stay close behind and keep the subject in sight at all times. When foot traffic is light, it may be best to cross to the other side of the street which is less likely to attract attention from the subject. Be on the lookout for any confederates of the subject as they may be watching to see if he/she is being followed. They may also be waiting to ambush you. Avoid the obvious giveaways: never peek over a newspaper, never sneak peeks from around a doorway. Avoid catching anybody's eye. Be confident. Your own mistaken belief that you have been spotted is more likely to give you away than anything else. If the subject speaks to you, treat him/her as you would any other stranger who did the same thing. If they accuse you of following them, deny it strongly, and say you think they have a mental problem.  If you are ever forced to abandon a surveillance, don't return immediately to your office. The subject or a confederate may be following you.

    In two-officer foot surveillance, some of the best tactics are to have one officer in front of the subject and another following from behind. Two officers can also LEAPFROG a suspect. In this method, one officer follows while the other moves well ahead, usually on the opposite sidewalk. At some point, the lead officer stops and waits for the subject to catch up with him. When the subject passes, the lead officer moves in behind while the backup officer moves ahead and becomes the lead officer.

    VEHICLES used for surveillance should be as unobtrusive as possible. Aerials, communications gear, and other equipment should not be visible. Headlights should be wired separately so the car appears differently at night. In city traffic, the best plan is to stay one or two cars behind the subject and far enough to the right so that the subject is not likely to notice you in a rearview mirror. In rural areas, you must lie further back and know the terrain. Two vehicles can also use the leapfrog technique.

    A three-officer or three vehicle tactic is called the ABC method. This allows the officers to change places from time to time, and cuts down on the risk of losing a subject. In foot surveillance, officer C is called the "rover" and walks along the opposite side of the street. In vehicle surveillance, officer C might be the plainclothes "jumper" who can get out of the car and blend into the foot environment easily.   In important cases where it is worth using more than two cars, the PERIMETER-BOX technique provides maximum security while minimizing the risk of detection. One car follows the subject, another leads, and another two maintain positions on parallel routes. Coordination is handled by radio. This works well in both urban and rural areas.

    Some of the things a subject will do to evade you include: trying to get lost in a crowd, boarding a bus just as it is about to leave, and entering a building by one door and leaving by another. Smarter subjects will go up to a uniformed officer and point you out as someone who is following them. If the officer delays you, the subject slips away; and if the officer lets you go, the subject knows that you are an officer too. Another trick is when the subject drops a worthless piece of scrap paper to see if you pick it up. A variation on this is when the subject goes up to a passerby, shows him or her an address on a piece of paper, and asks directions. The subject tries hard to make this innocent contact look like a suspicious transaction, and then watches to see if the passerby arouses suspicion and/or is followed. Almost any erratic behavior may be an attempt at evasion. The subject may drive down a one-way street the wrong way or make an illegal U-turn to see if you are determined enough to follow him.  If your suspect goes into a building to lose you, take out some fluorescent powder and rub it on your shoes. This way, your backup can track you if they have to. Otherwise, use your portable radio. At least one officer should stay in the lobby of the building, and other officers should cover as many exits as possible. If the subject takes an elevator, watch the indicator. Where the car stops, try to pick up the trail on that floor. If the suspect checks into a hotel, get the room number from the clerk and a record of outgoing phone calls. If the subject goes into a theater, race track, or ball park, the lead officer should attempt to sit right behind the subject. The same applies to bus rides, trolley, or subway. If you can't get in the vehicle with the subject, record the license number, company, place and time. The taxicab company will tell you the destination. If the subject goes into a restaurant, try to finish your meal first and pay your check shortly before the subject leaves.  If you suspect loses you in their own vehicle, when you catch up with the suspect again, feel the radiator to see if it's still warm. Also try to read the mileage both before and after a trip. Helicopter support is ideal for this, but many departments restrict usage to rundown situations.  If you lose your suspect, don't feel ashamed. They have more ways to lose you than you have ways to keep up. Just try to find the suspect again. Check the home and business address. Use pretext phone calls to family, friends, associates. Station an officer at the point where the suspect was last seen.

    REPORTS are especially important in surveillance operations. Each member of the team will have different facts, and these must be correlated to make a complete report. Reports should be detailed. Little things like discarding a matchbook are worth noting. Although your joint report should have differences between officers ironed out, it is OK to have differences of opinion in the report if they can't be reconciled. It is better to have too much information than to omit something that may be significant.


    Courts have always recognized surveillance as slightly un-American, but ever since Olmstead v. U.S. (1928), they have been attuned with public opinion that there are some times and places where privacy cannot be expected.  This changed with Katz v. U.S. in 1967 to a person-based conception of privacy, meaning that privacy exists when and where a person makes reasonable efforts to maintain it (reasonable expectation of privacy doctrine).  Also in 1967, the Court ruled that telephone surveillance was technically a "search" and by 1972, the Court was ruling that every single phone and wire tap needed prior judicial approval (although the government continued NOT seeking court orders when international communications were involved, on grounds that constitutional protections did not apply in these cases).  In 2001, with Kyllo v. U.S., the Court took another step at protecting domestic privacy, by banning police use of thermal imaging systems (and all future technology of that kind) on private residences.

    Ex parte and other court orders are required for any and all monitoring of conversations.  An ex parte order is good for only a short amount of time, and usually contains a minimizing requirement, which means that officers must cease their eavesdropping or spying as soon as the criminal activity related to the investigation stops.  They can turn their surveillance back on once the criminal activity starts up again.  Title III of the 1968 Omnibus crime bill still stands as requiring police to exhaust all other options before even thinking about surveillance.  A variety of other restrictions exist at the constitutional, statutory, and local levels.

    The Title III standard is probable cause (a crime has been or is about to be committed).  Title III did not adequately cover national security electronic surveillance, however.  That was addressed in the Foreign Intelligence Surveillance Act of 1978, which set up a special review court in Washington D.C., and made the standard a proportionality test (the benefits of surveillance outweigh the harms).  Current judicial doctrine also stresses the exhaustion test (standard investigatory methods have been exhausted, failed, are reasonably likely to fail, or are too dangerous to try).  Concerns about national security and domestic spying generally involve discussions of the FISA (1978) law and also the Communications Assistance for Law Enforcement Act (CALEA).  CALEA is for domestic wiretaps and FISA is for international wiretaps.  Each law requires a report to Congress every year, and each law requires a court order for every tap, although under FISA there is some leeway, including the possibility of getting court orders retroactively.

    Computer surveillance has some special regulations.  In 1986, Congress passed the Electronics Communications Privacy Act, which provides both civil and criminal penalties for violating Title III provisions. Subsequent legislation dealt with appropriation requests by the FBI (circa 1999) to install Clipper Chips on all newly manufactured computers, and then there was Homeland Security's 2002 plan to implement Total Information Awareness by scanning all networked computers.  The FBI managed to get approval in 2000 for CARNIVORE, which consists of boxes temporarily attached to the servers of recalcitrant Internet Service Providers (ISPs) which capture the header information from e-mail addresses of interest.  Great Britain's Regulatory Investigative Powers (RIP) bill allows similar machines to be permanently affixed to ISP servers, and that nation has also relied heavily upon fixed video surveillance by planting Closed Circuit Television cameras (CCTV) at places appropriate for monitoring populations of interest.  Facial recognition systems are often used in conjunction with this type of surveillance.  Roving wiretaps, which follow the person and not the equipment, and is an important consideration in the age of disposable cell phones and e-mail addresses, have been used since 1998.  The United States National Security Agency (NSA) is prohibited by law from domestic surveillance, so its ESCHELON program cannot be used to intercept electronic transmissions by citizens unless foreign traffic is involved or one of the foreign nations in an exchange agreement does it.


     Project Carnivore is part of a third-generation, online-detection software program called the Dragonware Suite, which allows the Bureau to reconstruct email messages, downloaded files and web pages. Historically, it has its origins in a 1997 program called "Omnivore" which ran on Solaris software and was incompatible with Windows (compatibility with Windows was not fully achieved until 1999). Although the FBI has provided minimal information to the public about Dragonware, and only a little more regarding Carnivore, the system is basically what is referred to as a "packet sniffer," a relatively common technology which examines or 'sniffs" packets of data streams on a network. Project Carnivore can only be utilized by the agency when a group or person is suspected of specified felonies, like terrorism, child pornography or exploitation, espionage, information warfare or fraud. Use of Carnivore is controlled under Title III of the Electronic Communications Privacy Act, so a court order is needed to utilize the tool as well as authorization by a "high-level" official from the Department of Justice before a local United States Attorney office can make an application to a federal court. However, there are "emergency" provisions whereby surveillance is permitted to proceed immediately, when high-level Department of Justice authorization is obtained, so long as a court order is filed within 48 hours.  Carnivore is not an information-gobbling monster that violates privacy.  It only allows law enforcement to read and record only that data which a court order authorizes, either "to/from" information or full email content.  It does NOT search thru the contents of every message NOR does it collect emails that contain certain keywords like "bomb" or "drugs."  It selects messages based on criteria expressly set out in a court order; e.g., messages transmitted to or from a specific account or to/from a particular user. 

    The Internet represents a vast "honey pot" of information for the government.  It has been trying for years to get Internet search engine providers (e.g., Yahoo, Google) to turn over their records, on fairly shaky legal grounds such as claiming to enforce the Child Online Protection Act (COPA) of 1998.  Such records would provide a window into the personalities of users -- what they want, what they dream about, etc.  Places on the Internet where a user has visited are kept in "cookies" that the search engines retain a record of.  Electronic privacy advocates recommend using software such as Tor and Anonymizer which hide a user's IP address (the string of numbers that identifies a user's computer) from search engines by routing search requests through a maze of servers.

    As opposed to Internet spying, when places or people themselves are wired for sound, this is usually called "bugging," and it is an entirely different subtype of surveillance than telephone taps, pen registers, and trap-and-traces.  For example, surreptitious entry or some degree of stealth are usually involved, the kinds of things we think about in terms of espionage. The U.S. Supreme Court in Dalia v. United States 441 U.S. 238 (1979) found nothing inherently prohibitive in bugging a premises as long as both the surveillance and surreptitious entry were judicially approved.  Wiretapping is the covert interception of communications content from telephones, telegraphs, fax machines, computers, pagers, wireless devices, and any circuit or packet switch. It is distinguishable from eavesdropping, another type of electronic surveillance, which involves intercepting conversations in rooms or between individuals in person.  In the United States, a pen register or trap and trace is authorized by the Electronic Communications Privacy Act of 1986 and similar statutes at the state level.  Pen/traps are easy to obtain and do (with telephone company assistance), very useful in a criminal investigation, and only have to meet a low legal hurdle, effectively relegating the role of the court to a ministerial function.  Full wiretaps are authorized by Title III of the Omnibus Crime Control and Safe Streets Act of 1968 and a smaller number of similar statutes at the state level. Wiretapping is also authorized under the Foreign Intelligence Surveillance Act of 1978. Pen registers are used the most frequently, followed by trap and traces as second in frequency of use, and full all-content wiretaps as the least frequently used.  In terms of numbers, there are about 75,000 pen/traps a year and only about 3,500 CALEA/FISA intercepts.  The USA Patriot Act of 2001 makes all Internet communications subject to pen register authority.  Authorization for a full all-content wiretap requires a proportionality test (the benefits outweigh the harm) and a bona fide intelligence purpose.  Authorization for a pen register or trap and trace requires relevance to an ongoing investigation, and in many cases, a judicial order is served on a service provider instructing them to cooperate with authorities.

    Wiretap law contains its own exclusionary rule. First of all, no wiretap can be used for quasi-judicial or administrative law purposes. This ensures that wiretaps remain a tool of last resort for serious crimes only, mainly felonies or activities that resemble organized crime, espionage, or terrorism.  Secondly, any application for a wiretap must be reviewed and signed by a politically accountable official before going on to a judge for approval. The case of U.S. v. Giordano 416 U.S. 505 (1974) made it perfectly clear that any rubber stamping of a political official's signature by their assistant would result in suppression of evidence.  Thirdly, there are documentation and notification requirements. Judges must be kept informed of progress, and upon completion, a full wiretap requires notifying all parties, at the time of charging with an offense, that their conversations have been intercepted. A judge, however, has discretion to decide whether other parties should be notified, and which other parties should be notified. The practical effect of this rule has implications for the number of civil lawsuits filed by other parties over the shock at finding out they were wiretapped.  Finally, there are executional and minimization requirements. At the time of executing a wiretap order, a professional effort should be made by officials to minimize the interception of irrelevant conversation. This goes beyond the standard protections afforded to privileged communication, such as that between husband and wife, and requires officials to ensure that irrelevant portions of the conversation are deleted and the most relevant portions are retained, all without being done in a manner that suggests the recording has been altered or fabricated in any prejudicial way.  Rules of evidence subject wiretap information to the authentication rule and best evidence rule. Unlike wiretaps, pen registers and trap and traces require no notice to persons that their communications have been intercepted. Nor is there any provision for judicial supervision of a pen register in progress. Also, there is no minimization rule.  


    There are about 50 different types of work which a police officer can be assigned to, and almost all of them rely or depend upon the authority of a uniform.  One of the most notable exceptions to uniformed duty is undercover work, arguably the most problematic area of law enforcement.  Undercover work is one of the most unique investigative techniques available to law enforcement.  The theory behind not wearing a uniform is that it removes any impediments to acquiring information.  It's part of the same intelligence-gathering function as surveillance, eavesdropping, use of informants, and espionage.  It typically involves an assumed identity for a defined and considerable amount of time.  Undercover work requires secrecy.  It allows the police officer to circulate in areas where the police are not ordinarily welcome.

    The job of the undercover officer is to "make cases", in other words, to gather enough information to enable a successful prosecution.  The purpose is not so much to obtain proof of criminal intent, the personalities or lifestyles involved, but to obtain physical evidence (by purchasing drugs or other contraband) and become the complainant seeking an arrest warrant.  Once the warrant is served, the officer's identity is usually revealed.  Ordinarily, a large number of arrests are made because the undercover officer has maximized their contacts as much as possible (e.g. with the drug or crime ring) on their own or by "converting" one or more of their contacts into informants.  A typical three-month operation may yield as many as 60 arrest warrants.


    Although there are many ways to initiate the undercover role, a typical pattern is to bring the undercover officer in as an acquaintance, business associate, or girlfriend/boyfriend of an informant, and then to distance themselves from that informant.  Once it's clear to all the parties involved that the officer is single again, another undercover officer is brought in as the boyfriend or girlfriend of the first undercover officer.  The key here is managing the informant because you don't generally want to take extra risks with an informant around when you don't really need them.  The ideal targets are the "big" dealers or criminals, but most officers usually start by going after the "small" fries, accumulating suspects and case material as they go.  The police supervisor, and sometimes, the prosecutor make a decision early on about whether enough "mid-level" or "big" cases have been made so that the operation can be terminated.  In most cases, the critical factor is continued safety of the officer(s).  Training of the undercover officer is sometimes nothing more than on-the-job training. Additional training may involve a few short hours of instruction on how to identify drugs, contraband, terminology, and prices.  Sometimes, a refresher course in criminal law and procedure is added.  A system is usually put in place for the officer to turn over evidence on a systematic basis or en masse at one time.


    Undercover officers usually are allowed to create their own cover stories, and depending upon the type of crime involved (drugs, guns, contraband, gambling, "subversive" groups), will eventually need more support from the department.  The need may arise, for example, to create false documents or computer records for the undercover officer.  This is not ordinarily done with minor cases.  The need may also arise for creating various kind of setup situations in which the undercover officer "proves" their criminality or loyalty by engaging in a staged showdown with regular police officers or other brush with the law.  The staged encounter may also be an opportunity to supervise the undercover officer.  Since supervision and continued surveillance becomes more difficult as the operation progresses over time, undercover officers are often "busted" to give a progress report and let management know if they need more or less supervision.


    Of all the kinds of police assignments, undercover work puts you at most risk of corrupting your integrity.  At some point, the undercover officer may begin to lose perspective, and become emotionally attached to this type of work.  This does not mean they become emotionally attached to the suspects, and become more criminal than cop.  It simply means that the department overall must think about maintaining its integrity by calling in anyone who has been doing this kind of work so that they can salvage their usefulness as a regular police officer.  Danger and temptation play roles in the late stages.  Undercover officers tend to get paranoid after a while, feeling like they have "cop" written across their foreheads.  They will begin to feel insecure and anxious about regular work and continued employment with the department.  They will often be amazed and astonished as some of the things they have experienced and the dangers they have faced.  Usually, they're carrying their own gun at this point for personal protection or they've arranged some other form of their own private surveillance and protection from real or imagined dangers. 

    If paranoia develops, the undercover officer may start having dreams about engaging in criminal activity.  They can't help it because subconsciously they succumb to temptation.  The problem is worse in drug cases because the officer may not be unable to decline the inhalation, ingestion, or injection of controlled substances, although by strict policy, they should make every attempt to avoid illegal consumption, even alcohol, during the operation.  However, if consumption occurs, one runs the risk of addiction, and the real possibility of neurological changes.  Anyone who engages in participant-observation runs the risk of "going native", and it takes tremendous self-discipline to keep from doing so.  Many officers end their undercover assignment when they feel "burned out" or express their first concern about being "made" or express a desire to surface and become a regular officer.  Supervisors normally do not try to talk anyone into staying undercover, although there is some concern for whether or not the appropriate cases have been made.  Most departments allow a "debriefing" period of time to help them adjust after coming off undercover assignments.


    In many cases, the undercover officer is new to the department, and something about their "looks" makes supervisors feel they are right for the job.  They may have been interviewed and identified for such duty while attending the training academy or while waiting on some civil service eligibility list, but generally, they finish up a rookie year or two first as a regular officer.  In rare cases, an applicant is sworn in secretly by the Chief and Personnel Officer the first day on the job.  The department may have some special need in an ongoing operation for someone who fits the "mold" and a new recruit may fit the bill.  Recruits from out of town are sometimes preferred, as are ethnic-looking recruits with foreign language skills and the occasional female.  The reason for using new, inexperienced officers is that you may not want someone who thinks, looks, and acts like a cop, especially for internal affairs operations or certain political targets.  You want someone who has still got a civilian mindset. 


    Just as some officers have the uncanny ability to spot criminals, some criminals have the uncanny ability to spot undercover officers.  Two things that will automatically tip any drug dealer off are: (1) familiar customers introducing strangers who want to buy drugs; and (2) small-time users who suddenly want to buy large quantities.  The idea behind requests for large quantities is to force dealers to contact their "connection."  Most professional criminals are keenly aware and ready for attempts to "flip" them over into becoming informants.  They will be prepared for this with bail money set aside and a lawyer on retainer to set up an entrapment defense, guarantees of immunity, and/or a written salary agreement.  Intermediate level criminals are also the group least likely to have addictions of their own.  Top level criminals hardly ever make mistakes.  The importance of combining undercover testimony with tape recordings or video recordings cannot be overstated, especially when dealing with a sophisticated criminal.

    At the other end of the spectrum, you have perpetrators who are easily caught up in a "reverse" operation where the police officer is the one selling the product.  Perps who usually get caught up in these kind of undercover operations are the small fries or "connections" who make stupid mistakes.  Almost always, the mistakes are made while intoxicated, high, or fatigued in some way.  However, even at this level, the criminal may make some attempt to "verify" someone's story, or check the undercover officer's cover out.  Two of the most common things checked out are family history and employment; these, and perhaps, an acquaintance or two. 

    How the undercover officer dresses and what they drive are also factors.  The clothing of drug addicts always doesn't fit right because they're constantly losing or gaining weight.  By contrast, most undercover officers can't simulate this particular "fit" of clothing; they'll only look sloppy and carry themselves like they have their "street uniform" on.  Scraggly beards that look recently grown also are a dead giveaway.  The cars they drive are also too well-maintained. A dope addict's car usually has three different types of tires, a bunch a hamburger wrappers all over the inside, and screaming kids in the back.  There's also the way undercover officers give themselves away with their eyes.  Their eyes are too full of life, and they seem to wear sunglasses all the time.  A dope addict, on the other hand, will often stubbornly or masochistically blind themselves by not wearing sunglasses even when they should, and their eyes will look sunken, like they haven't slept in days.  Other cover-blowing moves include: being too sure about the price; constantly making phone calls during a deal; being too overeager to buy; offering sex in exchange for doing business; being too familiar; and being too unfamiliar.

Association of Undercover Officers
California Narcotic Officers Association
Competitive Intelligence and Internet Information Gathering

Constitutional Guide to Using Cellmate Informants

Governmentality and the War on Terror: FBI Project Carnivore
Home Page of Prof. Gary Marx

How to Spot Undercover Agents
International Association of Law Enforcement Intelligence Analysts

International Association of Undercover Officers

Investigative Resources and Public Records on the Internet

Law of Undercover Operations
National Association of Legal Investigators

Police Use of Confidential Informants

Trace Anybody Online (Net-Trace People Search)

Undercover School Operations
Use of Informants in FBI Domestic Intelligence Operations (Cointelpro)

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Last updated: Sept. 27, 2011
Not an official webpage of APSU, copyright restrictions apply, see Megalinks in Criminal Justice
O'Connor, T.  (2011). "Informants, Surveillance, and Undercover Operations." MegaLinks in Criminal Justice. Retrieved from last accessed on Sept. 17, 2011.