It's rare that a prosecutor will admit at the outset of a Pittsburgh felony trial that they have no physical evidence.

But our Pittsburgh criminal defense attorneys understand that's just what happened at the outset of a recent trial for two men accused of shooting and paralyzing an area police officer.

There is no DNA. There are no fingerprints.

What the prosecutors contend they do have are two recorded confessions from both suspects.

But here is the problem that prosecutors may face: Confessions are often false, and a skilled defense attorney often has ample room to fight hem in court.

That said, it is never wise to offer a statement to investigators - under oath or not - without yuor criminal defense attorney present. It will almost never help your case, even if you're innocent.

There are a lot of reasons why someone would confess to something they didn't do, often referred to as a false confession.

In some cases, the defendant is trying to protect someone else, usually a friend or loved one. In other cases, they feel they should be punished for some other past wrongdoing. In other cases, the person wants attention.

More commonly than all of these, however, is the likelihood that police have coerced a confession. This often happens through aggressive questioning tactics which can be overwhelming to someone who has never before found themselves in that situation.

AlterNet.org indicates that of convictions that were later overturned through DNA evidence that wasn't available at the time of the trial, false confessions were present in about a quarter of the cases. Most police interrogations last an average of an hour or two. For those that led to false confessions, the interrogation time stretched on about 16 hours.

So confessions can be damaging, for certain, but clearly they're not full-proof evidence of anything.

In this case, the officer was shot in April 2011 as he stood at the back door of a home while responding to a report of a robbery.

The circumstantial evidence in the case is weak, and prosecutors know it, which is why they are banking on the confession.

The real lesson in all this is never to talk to police without your attorney present. But if you are charged with a crime based on a false confession, there is help.