Maria and Jack
Jack Daniel McCullough was convicted of the 1957 murder of Maria Ridulph.DeKalb County Sheriff's Department / Wikipedia

A former Washington State police officer convicted of a seven-year old's murder that occurred in 1957, has been freed from prison after new evidence has emerged. In the oldest case ever to be brought to an American court, Jack McCullough, 76, was handed a life sentence in 2012 for the killing of Maria Ridulph.

The child was abducted on 3 December 1957 from Sycamore, Illinois, roughly 65 miles west of Chicago as she played with her friend near her home. A man who identified himself as "Johnny" approached the pair before her disappearance.

McCullough, who once went by the name John Tessier in his youth, was one of 100 suspects interviewed by police at the time. Yet the 19-year-old was never arrested, as he told police he was in Rockford that day hoping to join the US Air Force.

McCullough was then arrested 50 years after the alleged murder after his half-sister, Janet Tessier, had disparaged him before she died in 1994, according to his mother. "Those two little girls, and the one that disappeared, John did it. John did it, and you have to tell someone," Janet Tessier is claimed to have said.

Following a police investigation, Maria's childhood friend identified McCullough as "Johnny" from an old photograph. McCullough was then questioned in June 2011 and a judge found him guilty after a week-long trial.

After serving almost four years in prison, a judge has now ordered Mr McCullough's release as newly discovered phone records support his alibi that he was at least 40 miles away the day Maria went missing. The review of the case was conducted by DeKalb County State's Attorney Richard Schmack.

Schmack said that his findings revealed "a wealth of information pointing to McCullough's innocence, and absolutely nothing showing guilt". On Friday 15 April, Judge William Brady agreed and made a decision to free McCullough.

Although he is now free for the time being, McCullough, will have to stand trial again for the murder. He said according to CNN: "Rest assured I am not trying this case ... You will not hear the words, 'Mr McCullough is guilty' or 'Mr McCullough is not guilty' coming from my mouth."

Despite the latest ruling Maria's family maintain that McCullough is Maria's killer . Her brother Charles Ridulph, 70, told local media the family feels let down by decision.