Again, no sign of Mitrice Richardson

One of the most extensive searches in the history of the Los Angeles Sheriff’s Department turned up no evidence of Mitrice Richardson, the young woman who has been missing since leaving the Malibu sheriff’s station Sept. 17.

The fourth fruitless search of the Malibu area left police and sheriff’s investigators mystified and family members clinging to hope that she is still alive.

“The beautiful thing about today is that they didn’t find a cadaver,” said Michael Richardson, 42, the father of the missing woman.

Searchers found no evidence of a crime scene either, “so this is still a missing person investigation,” said Sheriff’s Department spokesman Steve Whitmore.

“We’ll analyze what search and rescue did, brainstorm and see where we go next,” L.A. Police Det. Chuck Knolls said. He and Det. Steven Eguchi, who have been investigating Richardson’s disappearance full time since September, were recently joined in the task by several Sheriff’s Department investigators.

Richardson was arrested at Geoffrey’s, a restaurant in Malibu, after acting bizarrely, speaking gibberish and saying she could not pay her $89 dinner bill. Restaurant staff called deputies, who detained her at the Malibu-Lost Hills Sheriff’s station before releasing her at 12:30 a.m.

Richardson’s car had been impounded and she had no cellphone or purse. The last reported sightings of her were several hours later in Malibu Canyon.

On Saturday, 336 searchers, all trained, mostly volunteers, fanned out across the ridges, canyons and trails covering about 18 square miles east and west of the canyon, as far north as Mulholland Highway and south to the ocean.

Searchers came from Los Angeles as well as Santa Barbara, San Bernardino, Riverside, Ventura and Orange counties.

Mounted posses searched off-trail while other canvassers painstakingly scoured the area on foot, aided by dogs.

From a clearing near the command post set up in Malibu Creek State Park, the Sheriff’s Department’s Sikorsky Sea King helicopter picked up searchers to dispatch them to remote locations. Divers scoured the plunge pool in Rindge Dam.

Los Angeles police detectives investigating Richardson’s disappearance requested the more extensive search of Malibu after learning that the missing woman probably suffered from a bipolar disorder and appeared not to have slept in the five days before her arrest.

With this fourth search, Knolls estimates that 40 square miles of Malibu have been scoured for evidence of Richardson.

Although he said it’s a “good sign” that no remains were found, he noted the vastness of the Malibu wilderness and the inability to comb it completely.

Despite covering 18 square miles Saturday, he said he told Richardson’s family, “We didn’t look under every bush and every rock because you can’t do it. We wanted to make sure they understood that. They wanted us to definitively say she’s not out there. We can’t say that.”

In the nearly four months since the slender 5-foot, 5-inch 24-year-old African American woman was released from the station, the story of her disappearance has sparked outrage.

She was released not in a crime-ridden neighborhood but in a luxury enclave. Still, the area surrounding the lavish properties of Malibu is rugged, forbidding and unfamiliar to Richardson.

Last week, Sheriff Lee Baca met with Richardson’s parents for two hours to discuss their concerns and the circumstances surrounding their daughter’s release.

“This has a lot of different dimensions,” said L.A. County Supervisor Mark Ridley-Thomas, who called for a review of the Sheriff’s Department’s release procedures.

Ridley-Thomas said that although it doesn’t appear that deputies diverged from their normal procedures, “many advocates want to see heightened awareness of how the mentally ill are treated, particularly by law enforcement.”

But the controversy surrounding Richardson’s disappearance seemed to fade a bit Saturday as her father watched a helicopter thunder into the air.

“The big wings in the sky going off to search for my daughter,” he said. “It’s not a black thing, it’s not a white thing, it’s a human thing.”

carla.hall@latimes.com