The Trailside Killer of San Francisco

Mark McDermand

In a home not far from Mount Tamalpais on October 16, 1980, two people were found shot to death.  According to the court records, this is what occurred:  Mark McDermand, 35, and his brother, Edwin, 40, both resided with their mother, Helen McDermand, 75, in Mill Valley.  At approximately 8:30 P.M. sheriff's deputies forced their way into the home at the request of a concerned friend.  They found the body of a man lying in a hallway off to the left of the living room, whom they learned was Edwin. He had been dead approximately 12 hours, and several bullet wounds were evident in his head and chest.

In a locked bedroom was the body of an elderly woman, subsequently identified as Helen, lying on the bed and covered by a blanket. The body had a single bullet wound behind the left ear.  Scattered around the floor were eight spent .22 caliber casings: five near Edwin's body, one in the living room near the door to Helen's bedroom, one near a bookshelf between Edwin's and Helen's bedrooms, and one in Edwin's bedroom.

Looking around, the deputies went outside and observed a small, padlocked door leading into the basement. After forcing entry, they discovered a note tacked to the inner side of the door, addressed to "Shitheels" and stating that by the time the note was discovered, the reader would be "way too late;" the author would be found on the news or on a "slab." It was signed "Mr. Hate." 

This smelly, dirty basement area had been the bedroom of Mark McDermand.  He seemed a likely suspect, as there were spent .38 caliber casings in his room, along with three live rounds of .22 caliber ammunition, and ankle holsters for a handgun and a knife.

The coroner said later that while it was impossible to determine either victim's exact time of the death, samples of the vitreous humor fluid from their eyes suggested that both deaths had occurred from three to four days earlier. 

Within a few days, the local newspapers and the Marin County Sheriff and other members of his staff received letters from an individual who claimed responsibility. A handwriting expert testified that the author of these letters was the same person who had written the note tacked to Mark's bedroom door; the writer claimed he would not be captured alive.  Clearly he was following the news coverage, so the police devised a plan to lure him in: they indicated that if he surrendered, they would treat him fairly.  They ran a letter directed to Mark, giving him a phone number.