Reply #3: Not in this case.

[Moosepoop]

The cops in this case made an arrest, within hours realized they probably had the wrong guy, and called the prosecutor themselves to say so.

http://www.buffalonews.com/city/article101509.ece

The extraordinary move by law enforcement to change course after a murder arrest occurred after reviewing video and photos from the scene, and interviews with additional witnesses, Sedita said.

"What basically has happened," Sedita said, "is in the last eight hours ... we got additional video evidence. Investigators called me and said, Frank, you better come down here. We're having serious second thoughts.

"I looked at the evidence, along with four or five detectives, and the commissioner is here as well. There are certain discrepancies of people and clothing."

"I am going to probably ask the court to dismiss so we can continue the investigation, so we can be sure we have the right guy," he said.

There are way too many instances of police doing what you described, but this case isn't one of them.