Meanwhile, Leyva said, investigators are still looking into the possibility that a seizure played a role in the crashes but have not reached any conclusions.
Bryson, a key part of President Obama's economic team, went on medical leave on Monday night after reports surfaced that he had been cited for felony hit and run for leaving the scene of the first collision. A White House spokesman said Bryson suffered a seizure during the weekend but stopped short of blaming it as the cause of the crashes.
In his own memo on Monday night, Bryson made mention of "health issues that arose over the weekend" but got no more specific than that. He did not mention the collisions. A statement from the White House said he will spend his leave undergoing "tests and evaluations."
Bryson spoke to the president by phone on Tuesday morning for the first time since the crashes, according to pool reports. White House spokesman Josh Earnest said the president told Bryson to "focus his thoughts on his own health on his own family."
Leyva, the sheriff's commander, also told TPM the entire investigation will probably be handed over to the police department in San Gabriel, Calf., in the coming days because the chain of events began in that city. Currently, there are two separate investigations into the crashes, with the San Gabriel police investigating the first crash and the sheriff's department looking into the second.
Sheriff's investigators will continue to "collaborate with San Gabriel PD, but we'll probably hand it off to them," Leyva said.
A spokesman for San Gabriel Police Department did not return phone calls seeking comment.