Imagine going to prison for a murder you didn't commit?

In a Newsday/News 12 investigation, reporter Thomas Maier examines the case of Keith Bush and whether an innocent man was wrongfully convicted and if the real killer got away.

Keith Bush was 17 years old in January 1975, when Suffolk police charged him with killing Sherese Watson.

The 14-year-old girl was strangled and stabbed. Her body was found in an empty lot in North Bellport, not far, police say, from where the two had attended a late-night party.

Bush was found guilty of murder and attempted sexual abuse. He spent 33 years behind bars, all while trying to clear his name.

Turns out something was wrong. At age 61, Bush recently learned Suffolk authorities had another possible suspect.

Newly revealed documents show John W. Jones Jr., then a 21-year-old woodworker, admitted in 1975 that he was at the scene the night of the murder.

Jones said he tripped over the dead girl's body and left behind his plastic comb, which was found beside the victim.

Suffolk authorities never disclosed anything about Jones at Bush's trial. It would remain a secret for the next four decades, while Bush spent most of his adult life behind bars.

A News12/Newsday investigation found other signs that could point to Bush's innocence.

Forensic reports show male DNA found on the dead girl's body that wasn't from Bush.

There are also allegations that Bush's signed confession was the result of a police beating, something the department denied and a key witness who changed her story.

Maxine Bell says she was a scared homeless kid, afraid of getting in trouble, when she became the prosecution's key witness.

However, a judge ruled that Bell's accusations provided enough probable cause for Suffolk police to question Bush for hours in 1975. In the end, detectives got a written statement from him admitting guilt. Bush says detectives wrote it for him and beat him for hours until he signed it.

At his trial, Suffolk police denied any wrongdoing with the confession and at age 18, Bush was sent to state prison, insisting on his innocence and that the real killer had gotten away.

News 12 reached out to the top detective who handled the Bush case, but he declined to speak with reporters.

The prosecutor in the trial is now dead, and former Suffolk DA Thomas Spota said he didn't remember the case.