In the process of collecting evidence, police eradicated the evidence of fingerprints on the revolver that was found. The police smudged the fingerprints while picking up the gun, making the evidence inadmissible in court. However there were also fingerprints that were found and properly collected from the Tate's residence. The prints were found on the front door and on the inside of the door on the frame.
Fingerprint analysis includes the comparison of fingerprints found at the crime scene to a known set. This can aid investigators in determining the presence of a person, or people, at a crime scene. The process includes the matching of individual characteristics of the fingerprints. These characteristics include patterns such as loops, whorls, arches, and markings such as ridges, islands, bridges, and multiple other factors. What makes these characteristics individual is their location within the print.
During the trial, Paul Fitzgerald offered a weak defense. Fitzgerald suggested that the fingerprints found inside the Tate home may have just been an "invited guest or friend." On April 23rd, 1969, Charles Watson was arrested for public intoxication. During his arrest, his fingerprints were recorded. Watson's right-ring finger matched a print on the door frame which tied him to the crime scene. Charles "Tex" Watson was arrested in Texas on November 30th, 1969, when police received the notification that Watson's fingerprints matched those found on the door of the Tate home.