2 arrested at last in horrific beating of disabled homeless man

Tai Lam was a 67-year-old disabled homeless man who was kicked to death nearly two years ago in San Francisco as he slept in the middle of the night on Sutter Street in the Financial District. It was a savage and unprovoked attack by three assailants, and it was caught on surveillance video.

Everyone who saw the video and heard about the circumstances was outraged and disgusted. Then-police Lt. Toney Chaplin described it in 2014 as the most brutal killing he’d come across in his 25 years on the force.

The video shows the assailants kicking Lam in the alcove of a building where he had been sleeping. They pause when a car drives by, and then return to continue the beating. Lam was left suffering from his injuries and was found dead the next morning.

The suspects appeared pretty clearly on camera, so San Francisco police publicly released the least violent and graphic parts of the videos, hoping to get help from the public to identify the attackers. Nothing came, and the case seemed destined to remain unsolved.

Disabled and homeless, Tai Lam, 67, was beaten to death. Disabled and homeless, Tai Lam, 67, was beaten to death. Photo: Leah Millis / The Chronicle Photo: Leah Millis / The Chronicle Image 1 of / 7 Caption Close 2 arrested at last in horrific beating of disabled homeless man 1 / 7 Back to Gallery

But San Francisco police Inspector John Cagney, among others, refused to give up.

“I’ve been a cop for 25 years, 10 in homicide,” Cagney told me back in 2014. “This was terrible. They were stomping on him. They were drop-kicking the guy. And he absolutely did not do anything. He’s 100 pounds — a little, tiny, disabled (by polio) Asian guy.”

Monday, the investigative work paid off. Police arrested two 21-year-olds, Joseph Stull and David Peters. Stull was arrested in Idaho and Peters in Stockton. Both were booked on charges of murder, robbery, elder abuse and assault with great bodily injury. They’re being held in lieu of $5 million bail each.

Cagney declined interview requests, but department sources sketched out the details: DNA broke the case, but it took a while to get a match from evidence found at the scene.

One problem was that the evidence collected at the scene did not match any DNA records in crime databases police use to identify unknown suspects. That meant the assailants didn’t have felony arrests.

But the break came when Stull was arrested in Washington state on a stolen-car charge. A routine DNA sample was taken and entered into the evidence database, which helped SFPD’s crime lab get its match, police said.

Stull later ended up in custody in Kootenai County, Idaho, on charges of grand theft, possession of stolen property and more, and Cagney and his partner flew there to interrogate him on Sept. 21 for the Lam case.

Stull, police said, gave explicit details about kicking and stomping Lam, and told the investigators there was no provocation by Lam or interaction with him beforehand. It was a random attack.

Using Stull’s account, San Francisco inspectors identified Peters. In a joint operation with Stockton police, they searched a Stockton residence on Friday and found additional evidence that police said linked him to the crime. Peters also confirmed details of the assault and his participation, police said.

For Lam’s family, even convictions will never put this right. His brother, Harlan Lam, made many attempts to get Tai to come inside, but was rebuffed. When Lam was slain, Harlan Lam blamed himself for failing to get his brother off the street.

Although other members of the family will surely be pleased that officers believe they have closed the case, Lam’s brother never got the news.

In one last, sad coda to this awful attack, Harlan Lam, who was ill, passed away earlier this year.

C.W. Nevius is a San Francisco Chronicle columnist. His columns appear Tuesday, Thursday and Saturday. Email: cwnevius@sfchronicle.com Twitter: @cwnevius