Not so long ago, state usage of tools like drone cameras, smart license plate recognition and automated phone record analysis was confined mostly to national security services. These days, it’s not unusual to see suburban police departments putting these technologies to work.
So how are modern criminal investigations pieced together? Here’s the lowdown on some of the latest additions to the police toolkit.
The use of unmanned aerial vehicles (UAVs) is now common in virtually all aspects of police operations. Examples include shadowing targets on the move, foot pursuit support and exploration of high-risk or difficult-to-access places.
Drones fitted with thermal imaging cameras are used to identify cannabis farms.
Especially in light of the pandemic, we’ve also become familiar with drones being used to police large scale events and for crowd dispersal. Examples include the use of drones to issue dispersal warnings on crowded European beaches and to police curfews.
Can you tell the difference between a police drone and a regular one?
Is it a pair of police eyes above you in the park, or just a regular drone enthusiast? The companies who supply UAVs to hobbyists, industrial and commercial customers are often the exact same companies who supply the police. So unless the drone is issuing orders to you, it’s often impossible to distinguish police drones from other types.
Police drone privacy issues
Kitted out with powerful optics and thermal scanners, it’s easy to see how drones might be used to bypass protections against speculative searches. After all, why bother applying for a warrant to search a property when you can look through the windows and scan what’s inside from hundreds of meters away?
In federal systems, laws concerning drone usage can vary significantly from state to state. In the US for instance, some states mandate that police get a warrant before they use drones, otherwise any evidence obtained from them is inadmissible. Others (e.g. Vermont) have explicitly banned the use of drones to collect data on persons exercising their free speech and assembly rights.
Other states are relaxing their laws. Florida, for example, previously banned surveillance via drones without a warrant or the subject’s consent. A recent law made drone usage legal for law enforcement agencies to get an “aerial perspective of a crowd of 50 people or more”. It makes it easier for the police to fish for intel on lawful protesters.
Automated license plate recognition (ALPR)
How it works
The typical ALPR set-up used by the police usually consists of the following:
- HD infrared cameras. If these are portable ‘point and shoot’ versions, they usually connect to a display unit within police vehicles.
- The camera units deploy optical character recognition (OCR). It’s a form of AI that can instantly turn captured images into searchable script. OCR advances mean that ALPR systems are now able to “read” all kinds of plate variants and custom fonts.
- The system links up to a nationwide database of vehicle information, including directories of stolen vehicles. Officers can get an instant check on whether a scanned plate is of interest.
When ALPR crosses the line
A city-wide ALPR program can potentially do a lot more than just identifying absconders or uninsured vehicles. A networked system can capture plate numbers, images (including of passengers), precise geolocations, dates and times of every vehicle in its range, regardless of whether persons in the vehicle have done anything wrong.
If you are querying ALPR usage where you live, two questions to ask are…
- How long is this data retained? and
- Which law enforcement agencies (and possibly also private organizations) is it shared with?
Police tower dump
What is it?
Let’s say a crime has taken place but there are no definite leads. However, there’s a suggestion that the perpetrator used a mobile phone in the vicinity. If you can track down the phone used and it may lead you to the suspect.
One way around it is via a cell tower dump. A cellular network comprises numerous fixed-location cell sites (“cell towers”). Using these towers, the network continually tracks which phones are connected to which sites and locations at any given time. This cell site location information (CSLI) is logged and stored by cellular providers.
A tower dump is where the police request a network operator to turn over data about the identity, activity and location of all devices that connect to a particular cell tower over a specific timespan.
If you know when the crime took place and you just want to check if any phones were used in the vicinity, you might only need access to information spanning an hour or so. However, if you are less sure on the timescale, you may want to see data for, say, an entire weekend.
Especially where information is obtained for a wide timeframe, it means that data relating to potentially hundreds or thousands of mobile users are being harnessed - i.e. gaining access to the entire haystack to find the needle.
In some jurisdictions (e.g. the US), law enforcement agencies must obtain a warrant before obtaining cell phone location records from phone companies. In others, (e.g. India, the UK and Australia), a warrant is not required. Instead, a tower dump request is lawful if there are reasonable grounds to suspect that an offence has been or will be committed and the records potentially relate to that offence. In the UK for instance, it was revealed that the big four mobile networks had made customer data, including call records, available at the click of a mouse through automated systems.
The way forward
The ability of law enforcers to gather together huge tracts of potentially sensitive data is increasing - and this goes way beyond routine crime fighting.
Let’s say you are at a protest meeting, for instance. A small disturbance breaks out. The police use this as a trigger to request a cell tower dump, and in doing so, gain access to potentially useful information on the identity, movements and phone activity of people right across the crowd. Meanwhile, camera drones kitted out with facial recognition capabilities enable the police to figure out which other protests you have attended.
Wearing shades and a face scarf (as well as leaving your phone at home) isn’t necessarily about fashion: it’s about protecting your privacy.
There are always risks in challenging excessive police power, but the risks of not challenging it are more dangerous, even fatal.
We know that no one ever seizes power with the intention of relinquishing it.