Former army sergeant Stuart Jenkins has been acquitted of the murder of pensioner Arthur Brumhill in 1993.
The 41-year-old of Ossett in West Yorkshire, faced a 14-day trial at Northampton Crown Court.
But a jury has returned a not guilty verdict.
Arthur Brumhill was brutally beaten to death at Paul Denton Pet and Garden Supplies in Wellingborough Road on January 21, 1993.
Stuart Jenkins was arrested on suspicion of murder in 2015 after it was alleged newly discovered fingerprint evidence on a bag of straw tied him to the scene. He was 17 at the time of the murder.
But defending for the accused, William Harbidge QC said the prosecution case was “flimsy” as the jury could never be sure others were not responsible for Arthur Brumhill’s death.
In his closing speech, the barrister sought to dismiss the fingerprint evidence against Jenkins - suggesting the defendant could have easily placed his hands on the bag when he worked in the pet shop.
But he also pointed to evidence that there was another robbery in the Wellingborough Road area a short distance away from the murder scene that same night.
Witnesses saw two boys running in separate directions in the area at around 10.30pm that night and another suspicious-looking man was seen wearing a high visibility jacket acting "suspiciously". They could all be classed as suspects too, he said.
Furthermore, a man in a yellow tracksuit was seen in the area the next morning throwing away an object roughly 18 inches in length.
Updates to follow.