The Mobile Office: Field Tactics and Investigations

The Application of Research and Data can lead to felony Arrests

The introduction of mobile technology into law enforcement has increased dramatically. According to the Bureau of Justice Statistics, in 2000, 75% of local police officers and 61% of sheriffs' officers worked for an agency that used in-field computers or terminals, compared to 30% and 28% in 1990[i]. Just at the rate of application has increased, so has the sophistication of the equipment. Indeed, in the previous article we saw that police in-field computers have steadily graduated from “dumb” terminals to fully-functioning computers.

Sophisticated equipment has given the street police officer access to more and better information and provided him or her with a variety of means to capture information. Unfortunately, we may be somewhat lagging in our ability to apply that information in our field investigations and tactics. In this article we will explore some of the possible uses of technology in field investigations.

Hot Cars and Hot Data

On patrol you probably pass hundreds of cars each day. While an in-car computer gives you the ability to run each license plate you pass[ii], you just don’t have the time. Absent probable cause or reasonable suspicion to stop a vehicle, you can increase your odds of finding stolen cars and wanted suspects by narrowing your search. There is significant research that shows a strong correlation between crime and drugs, alcohol and age. Moreover, there is research to indicate that being under the influence of drugs or alcohol strongly increases the likelihood of arrest for both property crimes and violent crimes[iii].

One way to narrow your search is to go to locations where you know there is drugs and/or alcohol. As an example, try visiting all of the bars in your area an hour before closing. Drive through the parking lot and surrounding streets checking the vehicle license numbers. You will find a stolen car. And, you know when the suspect is going to return – at closing. By narrowing your search to an area with alcohol and vehicles, and then using the power of your in-car computer you have significantly increased the odds you will locate a stolen car.

Another tip is to look in motel parking lots. It will only take you a minute or so to glide through the parking lot and check the license numbers. The transient nature of motels often lends itself to drug sales and parties. I have often found that illegal activity tends to increase in “shabbier” motels between 0100 hours and 0400 hours. Locations that provide off-site sales of alcohol, just after midnight until closing are another good hunting ground for stolen cars and Driving Under the Influence arrests. A person making the last “beer run” of the night is very likely to young, under the influence and obviously not planning ahead.

Research indicates the peak years for committing crime are 17 to 21, steadily decreasing thereafter. Remember that we are not using the research to build probable cause or reasonable suspicion. We are using it to narrow our random use of the in-car computer. We are simply going to locations where there are likely to young males, alcohol and vehicles.

Warrants, Fugitives and Lies

The in-car computer has given us tremendous access to information from the National Crime Information Center (NCIC). Generally, when you check NCIC you are actually querying up to 22 separate databases containing over 66 million records[iv]. For instance, from your in-car vehicle NCIC gives you access to data about stolen vehicles, license plates, boats and guns. And, you can obtain information on wanted persons, missing persons and other fugitives.

As you uncover stolen vehicles you will run across vehicles stolen out of state. It is important for both your investigation and safety that you realize this is a different type of investigation. If you find a suspect driving a car stolen from out of your state you will not be booking them for the car theft. You will be booking them for being a fugitive from the state wherein in the car was stolen. So, you are not conducting a stolen vehicle investigation, but a fugitive investigation. As you articulate your reasonable suspicion to search the suspect and the vehicle remember the person is a fugitive from another state.

Before the advent of the in-car computer the number of people you could “run” for warrants was limited by the “air time.” Especially on night watch, you simply couldn’t run each and every suspect you stopped. Perhaps more importantly, you rarely had access to a suspect’s driving record. Now, with in-car computers, and as officer safety permits, both warrants and driving records can be routinely checked during field investigations.

Of course, many of the people we stop do not have identification. We rely on them to provide the information we use to check the various databases. And, as the old adage goes – garbage in/garbage out. Simply put, you can’t make effective use of the in-car technology without good information on the suspect. But, there are some ways you can use and perhaps store information in your in-car computer that may be helpful in determining a suspect’s true identify.

The first step in finding out someone’s true identity is determining the truthfulness of their statements. If you can figure out that the information they have provide is accurate you need go no further. Generally, social security numbers are issued by state. If you ask someone their social security number and they can at least remember the first three digits you can compare that information against the information about their place of birth.

Although there are a few people who are born in one state and move before they are issued a social security number, the tax law changes that require dependants over a year old to have a social security number has significantly reduced the number of people whose place of birth and place of social security number issuance do not match. If the suspect’s information does not match you have a clue that the information they are providing may be untruthful.

Click here to download a Social Security number issuance chart or astrological sign chart.

When a suspect does not have identification try asking for their parents full name before you ask them their name. If the suspect intends to conceal their identity they may have a ready made false name for themselves. But, you can throw them for a mental loop by asking for their parent’s names. They will either provide you with their parent’s real names (thereby short-circuiting their efforts to conceal their own identity) or their delay in answering may provide you with further evidence that they are attempting to conceal their identity[v].

Most databases that you access with your in-car computer query an age range. For instance, if you run a suspect with a date of birth in 1960, it will likely query several years each side of that year. So, by general appearance you have one third of the date of birth information you need to accurately check for wants and warrants. One technique you can use to verify information is to ask the suspect for their astrological sign. Generally, I ask this question a few questions after the date of birth question. If the suspect tells you they were born in October, but tell you they are a Pisces, you know they were likely to be born in late February or early March and not October.

If you in-car computer has a floppy disc drive you can download information like social security numbers and astrological charts. You simply make yourself a disc with all of the information you gather you can use this to check against self-reported information. Also, consider the use of a floppy disc to keep e-files on your penal code, vehicle code, etc. This will give you ready access to important information in your mobile office.

Information Imbalance Equals Danger

Officers working with a partner should employ the concept of “cover and contact.” That is, one officer is primarily responsible for contacting the traffic violator, suspect or witness and the second officer is primarily responsible to provide tactical cover. This clear division of responsibility greatly enhances officer safety and may ultimately strengthen investigations. The use of your in-car computer can unnecessarily distract you from the suspect(s). It is your partner’s (or back-up officer’s) responsibility to maintain control of the suspects and the surrounding are while you use the in-field computer. Remember, there are danger points during an investigation caused by the imbalance of information between you and the suspect. The suspect knows whether he or she is wanted. Points in time when the suspects feel you are distracted and attempting to verify their information are danger points. These are times that may motivate the suspect to flee or attack.

Police work is about information. Your in-car computer provides you access to a wealth of information. But, that information is only as good as your ability to creatively apply it. In the next article in this series we will look ahead at some of the developing technologies for the mobile office.

About the Author

Lieutenant Raymond E. Foster, LAPD (ret.), MPA is the author of Police Technology (Prentice Hall, July 2004); and the co-author of Leadership: Texas Hold ‘em Style (Quill Driver Books, September 2006), From NYPD to LAPD: An Introduction to Policing (Prentice Hall, January 2007) and, From Cold War to Flaming Hot War: Homeland Security and the Global War on Terror (Prentice Hall, July 2007). His complete CV can be viewed at Criminal Justice Profiles. Raymond can be reached on the Criminal Justice Online Forum or at mailto:raymond@hitechcj.com.


[i] Law Enforcement Management and Administration Statistics (LEMAS) 2000, Bureau of Justice Statistics
[ii] Generally, probably cause is not needed to randomly check licenses plates. For instance, in State v. Richter, 765 A.2d 687 (N.H. 2000), the court found that "Such a check is not a search subject to the protections of the Fourth Amendment to the United States Constitution. See State v. Bjerke, 697 A.2d 1069, 1073 (R.I.1997) (holding that a defendant had no reasonable expectation of privacy in a motor vehicle license plate). Nor does it constitute a search within the meaning of Part I, Article 19 of the New Hampshire Constitution. 'In considering what constitutes a search for purposes of our Constitution, we have stated that a search ordinarily implies a quest by an officer of the law, a prying into hidden places for that which is concealed.' State v. Summers, 142 N.H. 429, 432, 702 A.2d 819, 821 (1997) (quotation and brackets omitted). In no way can the visual inspection of a license plate mounted in public view on the front or rear of a vehicle be considered 'prying into hidden places for that which is concealed.' Nor can the officer's subsequent check of associated motor vehicle licenses and records, when 'the state is the very body that issues, controls and regulates' such licenses and records.” However, you should be guided by state and local law and policy.
[iii] Harrison, L. & Gfroerer, J. (1992). The intersection of drug use and criminal behavior: results for the National Household Survey on Drug Abuse. Crime and Delinquency. 38(4), 422-443.
[iv] Status of IDENT/IAFIS Integration, Report No. I-2002-003, Department of Justice, December 7, 2001
[v] According to NCIC, most databases are search and return information on phonetically similar names (e.g. Marko, Marco or Knowles, Nowles or derivatives of names such as William,Willie, Bill).