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Tuesday, May 27, 2014

Mobile phones as a retrieval tool?

Firstly, let me state completely and unequivocally, that mobile phones are NOT dCCTV retrieval tools. Secondly, let me say that using your mobile phone to record the screen of a DVR is not a good idea and the resulting file is not "the best evidence." In fact, your mobile phone footage is new evidence ... and might just be evidence of the misconduct of not properly securing the dCCTV evidence.

Rarely will you have so little time left before the DVR will cycle and thus erase your evidence. If the DVR offers no digital output options (rare event), you have other worst case options like connecting to an Ocean Systems Field Kit or seizing the DVR and processing the output in your editor. Or ... you can call and ask the help of a nearby agency with the tools/tech to help.

We should have as our goal the preservation of the actual evidence - the data that is within the DVR - using a method that preserves its integrity. Any other method, one that doesn't preserve the evidence intact, is problematic at best.

2 comments:

Sam Burgiss said...

Hi Jim,

Good post. Do you know of any other info explaining the "why" behind no recording the screen? I know some best practices don't specifically address this issue. They just suggest the other methods.

Thanks,
Sam

Jim Hoerricks, PhD said...

I tell folks in my classes to use this example: imagine going to a shooting scene and finding a pistol on the ground near a dead body. Then imagine taking a picture of the pistol, leaving the pistol on the ground and asking Ballistics to examine the picture. You can't do Ballistics on a picture of a pistol. You can't do DME analysis on a picture of DME.