Richard Royden Chamberlin admitted to firing BB guns at a Planned Parenthood facility in Pasadena almost a dozen times.
The drive-by shootings happened at least 11 times between 2020 and 2021. He also admitted to carrying a .22-caliber handgun during one of the attacks.
Chamberlin pleaded guilty to felony possession of a firearm and ammunition in a federal court.
In his plea agreement, Chamberlain said he intentionally conducted the attacks to interfere with the facility because it was providing reproductive health services including abortion.