Joan Rosenthal

Status:

Open

Jurisdiction:

Tiburon Police Department Marin County Sheriffs Department (CA)

Offense Location:

Tiburon, California

Summary:

Joan Rosenthal, a 75-year-old grandmother and community volunteer in Tiburon, California, was shot once in the head at her home on September 21, 2009. She was discovered by a friend in an enclosed patio outside her front door on September 22, 2009. Her murder remains unsolved.

Vital Statistics

Circumstances of Offense:

Joan Rosenthal lived alone in her home at 647 Hilary Drive in Tiburon, California, after the recent death of her husband Kenneth. On the evening of September 21, 2009, investigators determined she was shot in the head at approximately 9:00 p.m. She was found the next morning at about 9:40 a.m. on September 22 by a friend who made routine visits to the house. The friend discovered Rosenthal lying face down in her nightgown inside an enclosed patio just outside the front door. She was pronounced dead at the scene. Investigators ruled out suicide and found no signs of forced entry into the home. There were no apparent signs of a break-in and no obvious signs of theft.

Additional Details:

A $25,000 reward was offered one year after the murder for information leading to the arrest and conviction of the suspect. The reward was offered by anonymous donor(s) who worked through Tiburon resident and attorney Thomas Bertrand. The Marin County Sheriff's Department handled most of the investigation and spent approximately 4,000 hours investigating the case within the first year. Detectives traveled to New York City and Honduras to interview people connected to the family of Rosenthal's late husband. Shortly after the murder, the investigation focused on a party at a home adjacent to Rosenthal's residence the night before her body was found, but party guests were interviewed and no leads were developed. Because Rosenthal's body was found inside an enclosed patio behind a locked gate, police theorized that either Rosenthal let the killer inside, the killer had a key, or Rosenthal had stepped out of the enclosed area and the killer followed her back inside. In 2014, law enforcement investigated Max Wade, a Tiburon resident who was later convicted of other crimes, as a person of interest in the case. According to reports, Wade performed dozens of Internet searches related to the killing. However, Wade remained one of many possible people being investigated, and no charges were filed in connection with Rosenthal's murder. The case remained unsolved as of 2017 and beyond, with the homicide listed on the FBI's ViCAP database. Rosenthal was active at the Belvedere-Tiburon Library where she volunteered and organized book clubs. She had a master's degree in career counseling, taught classes at College of Marin, and was a trained speech pathologist. Rosenthal and her husband Kenneth had met in San Francisco in 1959 and were married for 48 years before his death from Alzheimer's disease in January 2009.

Case Last Updated:

Apr 23, 2026