Joseph Andrew Farnsworth was arrested Saturday on suspicion of shooting a Hells Angels associate to death on Highway 101

Joseph Andrew Farnsworth was arrested at a residence on Rheem Avenue in Richmond after Marin detectives arrived with a search warrant, said sheriff's Sgt. Keith Boyd. Investigators seized a 9mm handgun and are conducting ballistics tests to determine whether it was used in the killing.19-year-old El Cerrito man was arrested Saturday on suspicion of shooting a Hells Angels associate to death on Highway 101 last weekend, joining a 20-year-old Mill Valley woman in the Marin County Jail pending a court appearance Tuesday.The second suspect, Jessica Andrea Gordon, has been in custody since her arrest early Thursday. Authorities did not immediately release her name because of security concerns and efforts to "maintain the integrity of the criminal investigation," Boyd said.The suspected motive for the shooting is road rage."This appears to have no tie to any affiliations or relationship that William Maclean may have had to the Hells Angels," Boyd said of the victim.Maclean, 25, of San Leandro, was shot to death at about 8:15 p.m. May 24 on Highway 101 near Corte Madera. Maclean and Foakes were in a pickup that was leading a procession of bikers to Sonoma County after a Hells Angels funeral in Colma.Shortly after the convoy passed Tiburon Boulevard on northbound 101, there was a conflict in traffic and someone fired at the pickup from a red sport utility vehicle described as a Dodge Durango. Maclean, riding in the passenger seat of the pickup, was struck in the upper body.
Foakes, who was at the wheel, drove the truck to the Paradise Drive exit and called 911 from the pay phone at the California Highway Patrol's office on San Clemente Drive. Maclean was taken to Marin General Hospital, where he was pronounced dead.
Two suspects are in custody pending an initial court appearance on Tuesday. Jessica Andrea Gordon, 20, of Mill Valley was arrested early Thursday morning, and sheriff's investigators impounded a Dodge Durango from her residence.
Farnsworth was arrested Saturday afternoon after Marin detectives served a search warrant at a residence in Richmond. Investigators seized a 9mm handgun and are conducting ballistics tests to determine whether it was used in the killing.
The suspected motive for the shooting is road rage. The sheriff's department said Maclean's association with the motorcycle club does not appear to be a factor.
Investigators suspect Farnsworth was the shooter but have released no details about Gordon's suspected role in the incident. No charges have been filed.
"Ms. Gordon had no foreknowledge of the shooting, was in no way involved with the shooting, and is not guilty of murder," her attorney, Douglas Horngrad, said Sunday. "She, like everyone else, mourns the loss of life here."
As for Gordon's relationship with Farnsworth, Horngrad said: "Farnsworth, at most, is a casual acquaintance of Ms. Gordon's."
A public defender visited Farnsworth at the county jail Sunday afternoon. Public Defender Joseph Spaeth said his office had no comment on the case.