Lane-splitting has long been a controversial practice.
Considered acceptable by law enforcement in California, lane-splitting is all the more contentious when it leads to a crash that kills a motorcyclist.
Christopher Isaacs and his motorcycle were thrown under a big-rig and run over. The driver of the 2006 or 2007 Toyota FJ Cruiser did not stop.
Just a few days before the fatal collision, a law that went into effect gave the California Highway Patrol the green light to develop guidelines for motorcyclists who drive between lanes of vehicles. It represented a step that reinforced California's acceptance of lane-splitting.
The CHP is still developing the guidelines. Previous CHP recommendations advised motorcyclists to travel no more than 10 mph faster than traffic and to ride between vehicles only when traffic is traveling at 30 mph or less, among other suggestions.
Although lane-splitting is allowed, CHP Officer JIm Bettencourt said CHP officers can — and often will — take action against motorcyclists who do it dangerously by ticketing them for speeding or unsafe lane changes.
So far, the CHP has not been able to piece together all of the details of the crash that killed Isaacs. The Toyota driver who collided with him has not been found.
Bettencourt said speed played a role, but would not elaborate.
He said investigators followed up on leads to try to track down the driver, but to no avail.
"Nothing has panned out yet," Bettencourt said.
The Toyota driver, Bettencourt said, could face criminal charges, including hit and run — even manslaughter.
"We need everyone's side of the story, and unfortunately one person is deceased," Bettencourt said. "We certainly owe it to our family of the motorcyclist to piece together what happened."
He added that prosecutors ultimately would determine what charges, if any, to file against the driver.
Isaacs' family has not lost hope that the driver will be found.
"Christopher was one of those individuals that anybody and everybody who ever met him liked him," his father, Tim Isaacs, said. "We believe he would want people to know that motorcyclists are out there."
He added: "It's our children, our friends, our neighbors who are on the road."
The crash in Encinitas was not the first time Isaacs collided with a vehicle while lane-splitting. He had been charged with two misdemeanor hit-and-run charges in connection with a July 2015 crash on an off-ramp of Interstate 5 near Genesee Avenue in San Diego, according to the San Diego city attorney's office.
The case was dismissed after Isaac's death.
His father said Isaacs, who started riding motorcycles at age 18, was on his way to work when the 2015 collision occurred. Isaacs agreed to exchange information with the other drivers, his father said, but they wouldn't take it or share theirs until officers arrived. The young man, a south-central Idaho native who had moved to San Diego six years ago, decided to leave.
Tim Isaacs, who has been riding motorcycles for more than 30 years, said he is all for lane-splitting guidelines, as long as they take into account the interest and safety of all motorists. Lane-splitting is not a dangerous practice if everyone on the road drives safely, he said.
"We as a society need to start becoming responsible for our actions," he said.
While developing its guidelines, the CHP will consult with the Department of Motor Vehicles, the Department of Transportation, the Office of Traffic Safety and an organization focused on the safety of motorcyclists.
The CHP asked anyone with information about the fatal crash in Encinitas to call the agency at (760) 643-00 or (858) 637-3800.
Hernandez writes for the San Diego Union Tribune