The only problem was that there were no witnesses to the murder. however the police had recently started using fingerprinting in criminal cases. Only hours before his death, Hiller had painted some wood near his kitchen window.
The police found some fingerprints in the wet paint. During the trial, the police proved that the fingerprints belonged to Jennings, and he was convicted of Hiller's murder.Since then, fingerprinting has helped in the conviction of hundreds of thousands of criminals.