While thermal imaging is quite an amazing technology, the reality is that if you can't use it practically on the street, it really doesn't matter. Officers' cars and duty belts are already overloaded with stuff. Combine this with tight government budgets, and we can't afford to buy expensive, useless equipment. One of the fastest ways a thermal imager (TI) can earn your respect is to help you find a person who is either hiding from you or has fled from you, or has done both.
Why a TI?
Remember that the TI sees heat. Especially at night, this means the TI can be much more effective than a flashlight or spotlight. There are three main advantages the TI has over artificial light. The first is distance. A great flashlight might illuminate well to a range of 20 yards; a good thermal imager will view a human heat source from a range of 200 yards. Greater detection distance is clearly an advantage in locating and tracking the movements of a suspect, and it helps give you the upper hand.
The second advantage is that the TI detects heat. Even stupid criminals know how to hide from light--burglars wear dark clothing to make them harder to see at night. Fleeing criminals may hide in the shadows, knowing that it is more difficult for you to see them. However, most people do not understand how to hide their body heat. Think about the movie Predator. Arnold's character covers himself with mud to hide his body heat from the Predator. Why? The Predator "sees" heat, so even hiding in the shadows was insufficient protection. A thermal imager works the same way: shadows aren't enough; you actually have to hide your body heat. And few of the people we chase think like Arnold....
The third advantage is that a TI is passive--it receives energy rather than sending out energy like a flashlight. Because there is no energy leaving the TI, the suspect does not know if you are looking his way with a TI. Perhaps more importantly, an armed suspect cannot trace back the beam to figure out where you are, and open fire in your direction.
You are still wondering, "So, what does this have to do with patrol work?" Read on:
- Foot pursuit: Many criminals know when they are caught that they are going to jail. When we treat them fairly, they generally go peacefully. There are a small number of suspects, though, who prefer to go to jail "the hard way." They run after beating their spouses, bail out of a car during a traffic stop, or bolt when you get out with them on a street corner. Once you (or your more youthful partner) take off in pursuit, backup officers can use TIs to help track and locate the suspect. As the bad guy jumps and weaves his way through back yards, back up officers can monitor sections of the perimeter and look for his heat signature. That way, instead of following blindly in pursuit, and perhaps running into an unseen fence (been there, done that) or an ambush, officers can set up containment and then close in around the suspect in a coordinated manner. This improves not only the capture rate, but also the safety of the officers involved.
- Suspect in the Area: The Larceny from Auto, or LFA, is a Part I crime that gives patrol officers fits. How many times have you been dispatched to a report of a possible LFA in progress, only to arrive and find the suspects gone? The frustration comes from knowing that they are still lurking in the area. They hear your V-8 engine cruising up the street and duck into the darkness or behind a fence. They watch your spotlight bounce off obstacles nearby, and then return to their chosen profession when they hear your engine fade into the distance. LFA delayed, but not prevented; one more strike in the Compstat meeting. Light gives you away; they know when and where you are looking and can dodge you. A thermal imager, though, is covert. You can keep your vehicle stationary and darkened, using the TI to scan and monitor the area. Unusual heat sources near shrubs or popping out from behind cover will be excellent indicators of potential suspects. In fact, you can monitor the LFA-er's activity and movements, directing your partner by radio to his hiding spot. By operating in complete darkness, you give the LFA-er a sense of security. As a result, he goes back to "work" while you are watching.
- Fugitive from the Law: While the methodology of using thermal imagers to track fugitives is similar to that of a foot pursuit, the advantages of the technology are greater when searching for a fugitive. A true fugitive evokes images of a violent felon avoiding apprehension at any cost. Or, one imagines the motivated convict who has escaped from prison and is trying to disappear several states away. The fugitive is desperate, and therefore more dangerous. A fugitive will do almost anything to avoid going to prison, which makes him a threat to the public as well as police officers. As with a foot pursuit, the TI can help establish a perimeter to contain the suspect. Once the suspect is contained, a well-coordinated tactical approach can be made to pin him down and apprehend him. Containing the fugitive within a police boundary, then approaching him with superior numbers, greatly reduces the risk to civilians and officers.