An incident caught on video Thursday in which San Bernardino County sheriff's deputies beat an unarmed suspect marks the latest case of questionable law enforcement tactics at the end of a pursuit.
Even since the beating of Rodney King by Los Angeles police officers at the end of a chase more than two decades ago, law enforcement agencies have grappled with developing tactics that prevent arrests from getting out of control.
Experts have said that the end of a pursuit often marks a critical moment because officers' adrenaline is high after chasing suspects, who often drive recklessly, endangering others.
"Your adrenaline gets going, you get real pumped up. And you're still pumped up when you finally pull the guy over and get out of your car," one police officer told The Times in the wake of the King beating. "You have to make a conscious effort to downshift, so to speak, and to maintain control."
Many pursuits captured on video end without incident. But there have been recurring problems.
Just last year, the city of Los Angeles agreed to pay $5 million to the family of an unarmed man who was fatally shot by police at the end of wild pursuit in downtown L.A. Like in the San Bernardino case, the incident was caught on video by a TV news helicopter.
LAPD Chief Charlie Beck concluded that the officers violated department policy for using deadly force when they shot Brian Beaird, a 51-year-old National Guard veteran, on the night of Dec. 13, 2013.
In February, however, prosecutors declined to file criminal charges against the officers.
Back in 2004, the LAPD faced criticism after a news helicopter video showed an officer striking car theft suspect Stanley Miller 11 times with a large metal flashlight at the end of a 21-mile car chase. Investigators later found that another officer sparked the beating by yelling "Gun!" The officer later claimed he had felt a hard object, identified as a wire cutter, in Miller's pocket. A departmental investigation determined there had been no wire cutter in the suspect's pocket, though one was recovered from his car.
Police agencies have tweaked chase policies over the years for safety reasons. In certain dangerous pursuits, departments have ground units hold back, hoping the driver will slow down. Often, a police chopper will keep tracking the driver from above.
There were calls for better training of officers involved in pursuits in 1996 after two Riverside County sheriff's deputies were recorded clubbing two two people suspected of being in the country illegally, creating an international incident.
In Thursday's incident in Apple Valley, deputies are seen repeatedly kicking and punching the suspect at the end of a bizarre horseback pursuit. Video from a KNBC-TV news helicopter appears to show the deputies striking the man, identified as 30-year-old Francis Pusok, even after he was on the ground with his hands behind his back.
Sheriff John McMahon said he had ordered an internal investigation into the pursuit and a separate criminal investigation into Pusok's actions and those of the deputies who subdued him.
"It is disturbing and it appears on its face that there are violations of policy, but that will ultimately be determined in the investigation and to what degree," he said.
During the beating, which involved as many as 11 deputies and lasted for about two minutes, Pusok was kicked and kneed about a dozen times and punched more than two dozen times, the video shows.
The chase began about 12:15 p.m. Thursday when deputies arrived at a home in unincorporated Apple Valley to serve a search warrant in an identity theft investigation, according to a statement from the San Bernardino County Sheriff's Department.
Pusok was the "prime suspect" in the case, sheriff's department spokeswoman Cindy Bachman said, but when deputies arrived at the home, he was already in a car.
He fled, starting a nearly three-hour chase through Apple Valley and Hesperia, the department statement said. He led deputies through narrow trails and rugged terrain in Hesperia, requiring the California Highway Patrol and the sheriff's department to bring helicopters and motorcycle teams to help track him, Bachman said.
After Pusok fled his vehicle, he stole a horse from a group of people at Deep Creek Hot Springs, Bachman said.
A team of deputies came upon him around 3 p.m. near Highway 173 and Arrowhead Lake Road, sheriff's officials said.
Deputies used a Taser on Pusok but it "was ineffective due to his loose clothing," according to the sheriff's department.
Pusok had his hands behind his back as he lay on the ground when two of the deputies began striking him, including a kick to the groin, according to the video. More deputies soon arrived, and the video shows one trying to get one of the original deputies to step away from Pusok.
Pusok was taken to a hospital; his condition was not immediately available.
Three deputies were also taken to the hospital; two were treated for dehydration and one was kicked by the horse, according to the sheriff's department.
Former Los Angeles police Capt. Greg Meyer, an expert on police use of force, described the video as "ugly."
"This is a highly concerning video," he said.
Pusok had "obviously surrendered, followed commands to keep his hands behind his back -- that would be the time for the deputies to drop the knees on him and get him handcuffed," Meyer said. "But it didn't happen, and they will have to answer for the force they used on him."
Experts said the deputies' actions deviated from standard police protocol for arresting an accused felon at the end of a chase. Law enforcement officers are supposed to order the suspect to lie face down on the ground with their hands behind their back.