Center for Problem-Oriented Policing

Concrete Advice on Conducting Offender Interviews

The tradition of interviewing offenders has a long history in research and potentially strong application in policing. Really, police use interviews every day in investigations, custody, and on the street. What this guide provides is a set of procedures for you to utilize. We have identified 11 specific areas of concern:

  • Establishing the goals of interviews.
  • Choosing offenders to interview.
  • Determining who should conduct the interview.
  • Finding appropriate subjects.
  • Convincing subjects to participate.
  • Maintaining field relations.
  • Conducting interviews.
  • Sorting out the truth.
  • Analyzing the interview results.
  • Presenting the findings.
  • Applying the interview results to tactical and strategic problem-solving.

The Goals of Interviews

The goal of interviewing active offenders seems obvious: gain information that can help solve or prevent crimes. Things are not always as straightforward as they seem. The first decision to make is whether the goal of the interviews is to provide either tactical or strategic information. In tactical situations, information is gathered to meet short-term needs or ongoing investigations or activities. For strategic purposes, information from active offenders can be most useful in understanding motives, target selection, co-offending, or disposing of stolen goods. Using the knowledge gained through interviews with active offenders can function much like strategic intelligence in military settings. In addition, such information can play a useful role in planning and training.

Identifying what to ask can be the most important part of the process. The first place to start is with questionnaires that may have been used for a similar purpose. Most researchers are willing to share their questionnaires. It is important to consult someone experienced in making up such a questionnaire for advice on ordering of questions, how to ask questions, how to use "probes," and follow-up questions. It is also important to pre-test the questionnaire with several subjects before it is used for real.

Who to Interview

Determining who to interview is important as well. Not every suspect, person of interest, or arrestee can be interviewed; there simply isn't enough time or personnel available. High-rate offenders, particularly when they are not in a custody situation, can be among the most useful sources of information for strategic purposes. The field is an excellent site to conduct such interviews. Some custody situations, particularly shortly before release on bond or on municipal warrants, can also be productive. Just as the military debriefs captured enemy soldiers, you need to gather information from active offenders when they are in vulnerable situations and likely to talk, such as while recovering in the hospital, and facing sentencing or trial.

Many offenders may offer more information post­conviction, perhaps under conditions of community supervision, regarding other offenses than prior to conviction. It is important that interviews not focus simply on the characteristics of the current offense. Many burglars know a good deal about drug markets, the fencing of goods, and other forms of street crime. It is important to glean this information from them before they are released. In many cases, offenders are more willing to talk about offenses other than those that they are in custody for.

Interviewing active offenders provides a much closer look at offending than prison interviews. The offenders who end up in prison are a selective group, in a sense they are the "failures," the criminals who get caught. Interviewing active offenders makes it much more likely that the information about motives, techniques, and associations will be closer to the offense, and therefore more valid. Research has documented that active residential burglars who have not been caught go about the business of burglary differently than individuals who have been arrested and convicted. Having a routine and sticking to it was seen in interviews as the key to being successful. Such interviews and observations are important because they paint a different picture of offending than emerges from solely relying on police sources. Police respond to the most serious of offenses and offenders, often missing individuals at the earlier stages of their involvement in crime and with the criminal justice system.

Who Should Conduct the Interview

Much of the research that has been conducted with active offenders has shown that the choice of interviewers is very important. The two primary choices are to have police conduct the interviews in-house and contract with another group to conduct the interviews. There are advantages to both. For example, the police may be skilled at interviewing and have knowledge of details that could lead them to probe offenders in more detail. On the other hand, skilled outsiders may present less of a threat to offenders and gain more information. If you contract the interviews to a research firm or university-based team, clear and specific instructions regarding what is expected should be provided, and a questionnaire should be negotiated between the parties. The advantages of partnering with researchers to learn more should not be ignored. There are a lot of programs that operate in this manner such as the Arrestee Drug Abuse Monitoring system (ADAM) and Project Safe Neighborhoods. If you do commission the interviews to another group, be sure to specify the kinds of information that you are most interested in. This can be accomplished by reviewing questionnaires prior to starting the research process. Ethical concerns may dictate that non-sworn personnel conduct the interviews in cases where officers are involved in active cases that include potential interview subjects.

† As a general proposition, in the United States police may interview offenders about their general offending patterns and habits without triggering the requirements to notify suspects of their constitutional privileges against self­incrimination and access to legal counsel. You should seek local legal advice if you have questions about the legality of your interview plan.

The choice of interviewer is as important as the choice of the subject to be interviewed. Clearly, the value of subject knowledge is critical on the part of the interviewer. Equally important is the commitment to and ability to think strategically, searching for the appropriate applications of the information gleaned in the interview. The ability to probe for in-depth information, challenge a subject on inconsistencies or apparent falsehoods, and link across different kinds of crime are important qualities in an interviewer. Typically, these qualities are found in a veteran detective, though not always. Matching the race and gender of interviewer and subject is not critical, though it is desirable.

How to Find Appropriate Subjects

The police typically have no shortage of appropriate subjects: offenders with long histories of offending or subjects who associate with such offenders. However, you may want to expand the area where you search for appropriate subjects. Bodegas, convenience stores, car washes, fast food restaurants, vacant lots, street corners, areas in and around emergency room waiting areas, probation offices, alleys, and basketball courts may be appropriate "catchment" areas for you to seek out such potential subjects. In a sense, this advice represents an exhortation to meet offenders "on their own turf," where they are likely to feel more comfortable, and more importantly, be more likely to cooperate.21 Interviewing offenders while in custody can provide useful information, but even greater gains can come when the circle in which interviews are completed is widened to include their haunts.

Convincing Subjects to Participate

This is the key issue, a make or break proposition in the process of gaining useful information. Most of the successful research with active offenders has offered them incentives to participate, either in the form of cash (which seems to work best) or vouchers. In the research community, the principles of informed consent and Human Subjects Protection must guide such activities. Typically, the police are not in a position to offer such incentives. Many researchers have found that offenders often are anxious to talk about their own feats and those of others. After all, many offenders have a tendency to brag about their exploits or things they know of, but find few vehicles they can use to do so. The tradition of offering some compensation for information has a long history in policing in the use of confidential informants, but there can be other avenues in which enticements to discuss offending can be offered. You should consult with local legal counsel to ensure that any inducements offered to offenders do not violate laws, policies, or professional ethics.

† For U.S. federal guidelines on Human Subjects Protection, see the Code of Federal Regulations. [Full Text]

Informed Consent

Offenders interviewed should understand the purposes of the questions being put to them; the likely consequences to them for answering, refusing to answer, or answering falsely the questions; what, if anything, they will receive for their cooperation; their right to refuse to participate; and any other information that will enable them to provide informed consent to participate.††

†† The U.S. Code of Federal Regulations [Full Text] offers guidance on the requirements for informed consent.

Maintaining Field Relations

Once offenders have agreed to talk and provide information about crime patterns and techniques, it is important that communication be kept open. Some researchers reported that offenders would show up at their university after hearing from a friend that a study of burglary, robbery, or gang members was ongoing. Keeping subjects involved in an ongoing basis can pay particular dividends when the need for tactical information regarding a specific offense arises, and such subjects can play helpful roles in such operations.

Conducting Interviews

It is important that as much information be recorded in an interview as possible. Most researchers tape record their conversations with offenders and have them transcribed for analysis at a later time. This may prove to be impossible for many interactions between police and offenders, however taking good notes with appropriate detail is important. It is also important that the location in which the full interview is conducted does not place offenders at undue risk. Conducting interviews in plainclothes may allay some offenders' fears, and it certainly will not tip off the offender to others as an informer. Most researchers have found that doing interviews in public places was counterproductive, and some degree of privacy provided a safer and more useful set of information. It is important to note that these are interviews rather than interrogations.

Interviews can be conducted in groups, following a focus group methodology, or individually. There are some who argue that when offenders are interviewed in a group setting that there is less bragging and exaggeration, because others in the group will contradict someone who exaggerates. In addition, group interviews, particularly in a custody setting, can dispel fears about being labeled a "snitch" or a "stool pigeon." Others have found that interviewing one individual at a time is more likely to provide in-depth information and allows for a more "orderly" interview. There is no correct answer to this dilemma, however some advice can be offered. First, if the nature of questions is about group offending, such as gang activity or burglary, group interviews may make more sense. If the activity is more likely to be committed by one individual, then individual interviews may suffice.

Sorting Out the Truth

Researchers are sensitive to the claims that offenders may not always be truthful, by either bragging about offenses they did not commit or concealing offenses they did commit. Researchers generally have been careful to try and find means by which they can validate what they are told. This has been done several ways:

  • Sometimes this is done through repeated interviews and observations with the same research subject to look for the consistency of what the subject has said.
  • On other occasions, interviews with different individuals regarding the same event are compared to determine the extent to which they are telling the same "story."
  • A third method of validating responses is to compare offender responses to what is known from other groups regarding their behavior. Other groups can include police (using arrest records or field interview cards), schools, juvenile court workers, and other adults in the community.
  • Observations can be combined with interview techniques to determine whether a set of responses corresponds to other things that the researcher learns through observation.
  • In some instances, researchers have used official records, lie detectors, or urinalysis to assess the extent to which their subjects were telling them the truth. What has generally been found from such validation efforts is that like most people, offenders are not always truthful in reporting their behavior. In some instances offenders reported more crime and more arrests than official records checks revealed. 22

The ability of researchers to obtain valid information is enhanced by a number of factors. The first factor is the ability to enter the interview or observation setting with some knowledge of the behavior or community that they are trying to study. A second factor that enhances the reliability of such information is the use of multiple measures of the same concept. For example, an offender may be asked about gun ownership in a number of ways and on a number of occasions. The combined information will likely yield the most valid picture of gun ownership. Researchers can also rely on what is known from other sources of information about the specific behavior of interest. In this manner, crime reports, previous research, and a broader set of interviews with associates of the individual of interest may prove fruitful.

Analyzing the Interview Results

Interview results from a single offender are often quite useful. The real benefit from such interviews comes when several of them can be pieced together to form a larger picture of an offense. For example, the work by Wright and Decker (1994) with active residential burglars established patterns by which burglars got rid of the proceeds of their crimes, demonstrating the main categories of action as well as the variation within those disposal types. There are a number of software packages that can be used quite easily to sort through interview results, determine patterns, and create classifications. Such software can be used to analyze the text of police reports, where such reports exist in computerized text format. Here is an area where assistance from crime analysts can greatly enhance the utility of the analysis. These tools can help you to wring the greatest utility from information that can be costly to collect.

Presenting the Findings

One of the important things to do with information collected from active offenders is to transmit it to others within the police department, as well as other police departments and agencies of the justice system. Probation, parole, and prosecution may all find some utility in such information in the monitoring of offenders or preparation of cases. It is likely that police agencies face, to a large degree, some common issues. The goal of collecting such information is to end up with a product that is useful and can be applied in a wide variety of circumstances. Nothing detracts from the utility of information like having it presented in an unintelligible or overly complicated manner. Summaries with key points in bulleted form, a simple graph or two, and suggestions about action steps are the surest way to ensure that information becomes action.

Like any analysis, findings should be presented around key concepts and themes. These concepts and themes should be drawn from the focus of the problem-solving initiative. Summaries of what an individual subject said are generally less helpful than summaries of what all the subjects said about a particular subject. Many researchers have found that discussing their findings and conclusion among themselves, and then with their research subjects has been very productive.

Applying the Interview Results to Tactical and Strategic Problem Solving

The products of interviews with active offenders can be quite useful. As noted above, one of the key issues that has been learned from these interviews is the role that lifestyle plays in offending. Interviews and observations hold the promise of uncovering more of that lifestyle than simply interviewing offenders in prison. Such interviews and observations are important because they paint a different picture of offending than emerges from solely relying on law enforcement sources. In addition, interviews have shown that offenders do not always perceive the cues in ways that we expect. Determining their perceptions can be the key to successful interventions.

There are numerous examples of differences between the picture of offending and offenders that police and field research have revealed. Paying attention to interviewing and more thorough debriefing of offenders can help counterbalance such biases, and provide information that would lay the groundwork for better problem-solving.

The work of the Plano, Texas police department is a good example of the application of these principles.23 Having determined that underage drinking was a problem in Plano, an officer assigned to problem-solving conducted interviews with clerks in package stores. These interviews revealed a lack of fear of being caught for underage drinking, coupled with limited knowledge of the laws governing sale of alcohol to underage minors. This information was used to pilot an informational campaign to raise awareness of the law and penalties attached to the laws against the sale of alcohol to minors. Sales to minors decreased significantly. In Lancashire, Great Britain, police officers observed a serious problem with cocaine and crack use. Interviews were conducted with the 10 individuals most involved in such drug use and offending such as robbery, burglary, and auto crimes. These interviews determined that there was a lack of connections between offenders and treatment. As a consequence, police worked to fix the gaps in the system of linking offenders to treatment services, as well as hold these individuals accountable for their behavior. A 30 percent reduction in crime was recorded.24

The successful Boston Operation Ceasefire used interviews with active gang members to determine preferences for guns and assess the role of drug dealing in gangs. 25 The results from these interviews changed the focus in gun interdiction strategies and led to the use of directed patrol against gang drug sales when shootings erupted.

Numerous other examples of the successful use of interviewing active offenders by police agencies can be found. These examples include many POP projects that have received recognition for their impact. They include the use of interviews with prostitutes in the Lancashire Constabulary26, with "johns" and prostitutes in Buffalo27, and with burglars in Chula Vista, California.28 In each case, these projects illustrate the feasibility as well as the impact of such an approach. Interviewing active offenders can enhance existing POP projects or generate new ones. In either case, the information gleaned from active offenders can provide important strategic information to change interventions or generate knowledge.