So says a very glib law professor (video), and then the cop he calls up afterwards (video) says the same thing. These are each 20 minutes but they are really interesting; you would be surprised at how even someone who is totally innocent, makes truthful statements, and even has the interview videotaped, can end up incriminating himself by talking with the police.*
I was surprised that nobody brought up the fact that police need to rely on civilians to gather information in order to solve crimes. I don't know if the professor meant, "Don't talk to the police when you are a suspect" or if he really meant, "Don't ever talk to the police when they are gathering info about a crime." Either way, it just shows why shady police tactics are self-defeating. Lying to a suspect may get him behind bars, and if the police are "sure" he's guilty you might think that's fine, but as more people become aware of these practices, it makes it harder to catch true criminals in the long run.
* Let me give the news you can use for those without 20 minutes to spare: Suppose the police bring you in for questioning, and in the patrol car you hear them discussing how witnesses heard 4 shots fired. Then they get you into the interview room and start rolling the tape. You say, "I had nothing to do with this shooting. In fact, I was 10 miles away when it happened."
Even if that is true, what happens when the DA puts that cop on the stand, plays your statement for the jury, and then says, "Officer Smith, did anything strike you as odd about his response?"
"Why yes something did."
"And what was it, Officer Smith?"
"We had never told him there had been a shooting. We just said we were investigating the murder of Mary Adams."
Then your attorney tries to do damage control by putting you on the stand, and you say the cops in the patrol car mentioned a shooting. They put both those cops up on the stand, and they deny ever having said that in your presence.
So now the jury thinks you have been caught with knowledge of the murder beforehand, and now lying on the stand. Oops.