See Jennifer Mnookin's Op-Ed on the recording of confessions.
Extract:
Supporters of the practice present recordings as a solution for a host of problems, from police misconduct to false confessions. But while there are lots of good reasons to require them, they are hardly a panacea; in fact, the very same qualities that make them useful — their seeming vividness and objectivity — also risk making them misleading, and possibly even an inadvertent tool for injustice.
&&&
The dynamic evidence page
Evidence marshaling software
MarshalPlan