Mary Alice Siem

Mary Alice Siem was a student at the University of California, Berkeley who was one of the founding members of the Symbionese Liberation Army (SLA), an extremist group known for the kidnapping of heiress Patty Hearst.

Siem was known to have visited both Donald DeFreeze and Thero Wheeler while they were in prison, prior to their escapes. She was considered to be Wheeler's girlfriend and a frequent visitor to him at the prison. After Wheeler's escape, Siem began hanging out with Mizmoon and Nancy Ling Perry. She is believed to have left the SLA soon after the escape of Thero Wheeler from prison. On February 18, 1974, police in Redding, California, sought Siem as a "known acquaintance" of two escaped convicts (DeFreeze and Wheeler). She was described in the press as a young heiress, 24 years of age.

On 4 May 1974, an article appeared in The Pittsburgh Courier quoting Siem. She had originally spoken to The San Francisco Examiner. She said that she had left the SLA due to death threats from DeFreeze:

Mary Alice Siem, 24, Redding, Calif., told authorities she and Thero Wheeler, 29, unofficially identified two months ago as a possible suspect in the Hearst kidnaping, left the terrorist organization last October because they disagreed with the SLA's violent tactics.

Miss Siem ... said she and Wheeler, who were living together, attended about 20 SLA meetings. ...

On one occasion she said she was threatened at gunpoint by DeFreeze, Miss Soltysik, and Miss Perry, but Wheeler intervened. When they left the SLA, she said she and Wheeler were robbed of $600 by the other members.

According to the examiner, whose president and editor is Miss Hearst's father, Miss Siem told authorities that she and Wheeler left the SLA because Wheeler was opposed to the violence espoused by DeFreeze.

She said their departure took place in October, a month before the fatal shooting of Oakland Schools Superintendent Marcus Foster, for which the SLA claims responsibility, and four months before Miss Hearst was kidnaped.

• Burrough, Bryan (7 April 2015). Days of Rage: America's Radical Underground, the FBI, and the Forgotten Age of Revolutionary Violence. Penguin Publishing Group. ISBN 978-0-698-17007-0.