DNA samples from every man in Bristol should be screened as police continue to hunt for the murderer of Joanna Yeates, one of the city's MPs has urged.
The policeman agrees - even if you are innocent and know you are innocent and know you can prove it, speaking up can get you a conviction. Watch the video to see how. (The policeman speak out in part 2).
I will admit to not following his advice many times since having watched it. I recognise the principles, but I also recognise that police who I have had occasion to speak to me have had no or little interest in prolonging the conversation, so my strategy was to avoid changing that. i.e. shut my mouth, listen, and say sorry and thank-you.
In abstract, the lawyers advice is the same, but he explains how often you won't know how to encourage disinterest on the part of the police.
I realised that the OTHER video is missing, the one that shows you the trouble people got into for not talking to the police in cases where you were innocent. We can only speculate what it would contain if it were made.
This guy helped police with DNA and had slight problems. The conversation with the police was funny: http://www.circulartriangle.com/blog/?p=41