CCTV monitoring is managed by local police and councils from the local boroughs. In London alone there are 32 boroughs, which means that if you wanted to collect your video tapes from your trip you would have to deal with however many boroughs you traveled through. Luckily there is a CCTV code of practice which offers recommendations on how to use the equipment. Recommendations range from assuring a suitable quality image to protecting the recordings from corruption. The code also recommends that there be a regular check to make sure the date and time stamp recorded on the images is accurate.

We are not sure how these local boroughs are maintaining their time, but we certainly hope it’s not by manually setting it. This is a problem for several reasons. If all we were concerned about was one centrally located station that managed all of the CCTV cameras, then once they acquired their time, chances are all the cameras would be synced to the same time. However, if all the different boroughs are checking and correcting their times manually at different times, then the likelihood that they are all synchronized to the same time is pretty remote. This could be problematic if the police want to splice together video recordings from adjacent boroughs to use for evidence in a case. For example, the suspect could be on one video camera at 1:05 p.m. and walk into the next video camera which is managed by another borough, but its time stamp says 1:03 p.m. Even though the video footage shows the suspect, the discrepancy between the time stamps ruins the evidence.

The Scientific Working Group for Imaging Technology (SWGIT) developed guidelines for good practices for the use of imaging technologies within the criminal justice system. Its’ goal is to engage the entire law enforcement imaging community in the implementation of these guidelines. When it comes to time synchronization and time stamping the SWGIT recommends the use of Network Time Protocol (NTP) for IP-based systems and GPS-based timing equipment as an industry-standard time synchronization method.

This recommendation can be achieved with a simple and relatively inexpensive solution: an NTP time server which acquires time from GPS, like the SyncServer S300. If all of the boroughs were equipped with these time servers, then they could be assured that every camera’s time code would be synchronized to the identical GPS-acquired accurate and provable time. Who knows? This small but significant improvement could help increase the number of crimes solved using CCTV.