Police discovered that Jones's fingerprint was on the teacup found at the farmhouse, despite him and Cheryl denying that he had ever used it. This suggested that Jones was the mysterious visitor who appeared at the Tooze farm on the day of the murders, especially since he was a close associate of the Toozes and a surprise visit might have necessitated their use of the good china. Apart from Harry and Megan's own fingerprints, only Jones' fingerprint was found on the items at the scene.
