The Case of Mary Louise Cannon

Mary Louise Cannon was 75 when Richard Ramirez attacked her inside her Arcadia home on July 2, 1985. She was found dead after being beaten and stabbed during a home invasion. The killing was one of several attacks committed by Ramirez against residents in their homes as his Southern California crime spree intensified.

Mary Louise Cannon lived alone in Arcadia, California. By July 1985, Richard Ramirez had already been linked to a growing series of murders, sexual assaults, robberies and home invasions across Southern California. Investigators were increasingly concerned that a single offender was responsible, although Ramirez's identity was still unknown. Cannon became one of the older residents targeted during the Night Stalker's 1985 crime spree.

Ramirez entered Cannon's home during the night and attacked her. She was beaten and stabbed during the assault and was found dead inside the residence. The attack was consistent with the increasingly violent pattern being seen in other Night Stalker crimes, in which Ramirez entered occupied homes and attacked residents with a combination of physical violence and weapons.

Cannon's murder was investigated alongside the rapidly growing number of attacks being committed across Southern California. By this stage, investigators were comparing evidence from different jurisdictions in an effort to determine whether the same offender was responsible for the seemingly unrelated home invasions. After Ramirez's arrest in August 1985, investigators reviewed evidence from the various crime scenes and connected him to Cannon's murder. The case was subsequently included among the murders prosecuted during Ramirez's 1989 trial.

Richard Ramirez was convicted of murdering Mary Louise Cannon in 1989. The conviction formed part of the 13 murder convictions that resulted in his death sentence. Ramirez remained on California's death row until his death from complications of B-cell lymphoma at San Quentin State Prison on June 7, 2013.

Cannon's murder occurred during the final weeks of Ramirez's crime spree, when attacks were increasing in frequency and investigators were working urgently to identify the offender.