In 1974 - 12 years after the murders of Tim and Joyce, a man with no prior criminal record, Bill Macumber was arrested and tried for their murders. Macumber's ex-wife, who worked for the investigating Sheriff Office provided testimony and questionable evidence that got him convicted. Sentenced to two life terms, he spent the next 37 years in prison before being released on a legal "plea deal" - although he always denied having killed the couple.
Here is some information known to investigators in 1964, but NOT made known to the prosecution or defense lawyers during Macumber's 1974 trial.
Who really killed Tim and Joyce?
"Ernsesto Valenzuela told police in 1964, when he was arrested over the fatal shooting of another young couple, that he was responsible for the Sterrenberg/McKillop murders in 1962.
A female eyewitness, Linda Primrose, also told police that she has seen the killer, describing him as a young man, 5'9 in height and around 160lb.
Police had earlier dismissed Valenzuela for the murders, believing him to be a 'kook' who dreamed up all manner of confessions.
Following the second murders, which attorney Mr Green described as having similar 'lover's lane' style traits to the Sterrenberg/McKillop killings, Valenzuela was convicted.
He also confessed to the 1962 murders to several prison psychiatrists who classed Valenzuela as a homicidal maniac.
Valenzuela died during a prison riot in 1974 after he was convicted for the two separate murders - but the Sterrenberg/McKillop case remained open.
Despite the fact Valenzuela's attorney came forward to support his dead client's confession, neither the prosecution nor the defense was privy to the information in 1974 during Mr Macumber's trial."
LINK:
Bill Macumber: Man, convicted of double murder in Arizona, released after 37 years | Daily Mail Online