Authorities have shared grisly details of the deaths of a family whose SUV plunged off a cliff in California, including how their bodies were retrieved and how the children had drugs in their system.

The details were revealed at a coroner's inquest on Wednesday in a bid to determine whether the March 2018 deaths of Jen and Sarah Hart and their six adopted children were accidental, a murder-suicide or undetermined.

The crash happened just days after authorities in Washington state, where the family moved in 2017 from Oregon, opened an investigation following allegations the children were being neglected.

A neighbor of the Harts in Woodland, Washington, had filed a complaint with the state, saying the children were apparently being deprived of food as punishment.

The details were revealed at a coroner's inquest in California on Wednesday in a bid to determine whether the March 2018 deaths of Jen and Sarah Hart and their six adopted children were accidental or a murder-suicide. Sarah and Jennifer Hart (behind) with their six kids

The bodies of Jen and Sarah were inside the SUV when it was discovered but one of the women fell out as the vehicle was being towed up the cliff off the coast of Mendocino County

No one answered when social workers checking on the report went to the family's home near Portland, Oregon, on March 23.

Three days later, their SUV was found partially submerged on the ocean below a rugged cliff.

Google searches were read by California Highway Patrol Officer Jay Slates during the Mendocino County coroner’s inquest presented by the Sheriff’s Office Thursday.

'How long does it take to die from hypothermia in water while drowning in a car?', Sarah also searched, according to Slates’ testimony.

Sarah began searching at 12.30 am on March 24 as she and her family neared the Washington-Oregon border.

She would continue to conduct Google searches along these lines until 6:30 p.m. that night.

The bodies of Jen and Sarah were inside the SUV when it was discovered but one of the women fell out as the vehicle was being towed up the cliff off the coast of Mendocino County.

Sheriff Deputy Robert Julian testified on Wednesday that he was able to identify Sarah Hart through a Minnesota driver's license found near the car.

'I wasn't able to identify Jennifer Hart due to her fall,' Julian said.

The bodies of siblings Markis, Jeremiah and Abigail Har were found the same day near the car.

Weeks later, the body of Ciera Hart was pulled from the Pacific Ocean and human remains found in a shoe were matched to Hannah Hart through DNA testing.

The remains of 15-year-old Devonte Hart have not been found.

The bodies of Jen and Sarah were inside the SUV when it was discovered but one of the women fell out as the vehicle was being towed up the cliff off the coast of Mendocino County

The crash happened just days after authorities in Washington state, where the family moved in 2017 from Oregon, opened an investigation following allegations the children were being neglected

Jennifer was drunk when she drove her large family off a Northern California cliff, authorities said.

Greg Pizarro, a forensic pathologist, testified on Wednesday that an autopsy found she had an alcohol level of 0.102. California drivers are considered drunk with a level of 0.08 or higher.

Pizarro said her cause of death was a broken neck.

Her wife, Sarah, and several children had large amounts of a drug in their systems that can cause drowsiness, authorities have said.

The family's SUV plunged off a seaside cliff more than 160 miles north of San Francisco.

Sarah pleaded guilty in 2011 to a domestic assault charge in Minnesota over what she said was a spanking given to one of her children.

Oregon child welfare officials also investigated the couple in 2013, but closed the case without taking any action.

Jennifer was drunk when she drove her large family off a Northern California cliff, authorities said. Her wife, Sarah, and several children had large amounts of a drug in their systems that can cause drowsiness