A lawyer killed herself and one of her daughters in a crash on a Devon road while more than three times the drink-drive limit, an inquest heard today.

Veronica Morley, 47, also had a high level of sedatives in her system when she lost control of her car and crashed into trees down a steep bank.

The solicitor, who worked for the Metropolitan Police, had a history of alcoholism but had told her family she had stopped drinking.

The crash happened as she drove home to London with her two daughters, Zoe, 12, and Imogen, 14, after a half-term break in Cornwall.

Mrs Morley suffered fatal head and chest injuries and Zoe died from head injuries when the car went out of control on the A30 in Devon on October 25, 2008.

Imogen survived virtually unscathed and clambered from the wreckage.

Both daughters had rear seat passengers in the red Toyota Yaris and all three had been wearing their seat belts.

The inquest at County Hall, Exeter, resumed today after Exeter and Greater Devon Coroner Dr Elizabeth Earland had adjourned a previous hearing in November last year in order for further inquiries to be made.

Witnesses described seeing Mrs Morley, who lived in Dulwich, south-east London, veer across the carriageway, near Woodleigh Junction at Cheriton Bishop, before hitting trees.

Mrs Morley’s mother, Patricia Castle, said in a statement to the court that she was aware her daughter had been drinking a lot of wine but “had stopped drinking six months ago”.

She said: “She would never put the lives of her children at risk or in danger.”

Mrs Morley’s GP said the lawyer had used alcohol to help her sleep but had become dependent on it.

She was not suffering depression but was using sedatives to try to help her sleep.

Consultant toxicologist Stephen George said blood tests taken after Mrs Morley’s death showed she had a blood alcohol level of 256mg of alcohol in 100ml of blood. The legal limit is 80mg per 100ml of blood.

There were also large traces of diphenhydramine – a powerful sedative found in Nytol sleeping tablets – in Mrs Morley’s system, he said.

Mr George was asked whether the combination of drugs and alcohol would have affected Mrs Morley’s driving.

Reading from his report, he said: “I have stated there would have been serious impairment to the consciousness level and judgment of an individual.”

The inquest heard police crash investigator John Hitchcock say it was a possibility Mrs Morley had just fallen asleep at the wheel.

He concluded that the exact reason for the crash had not been established but the high levels of alcohol and sedatives could have impaired Mrs Morley’s driving ability, judgment and perception.

He said that due to the amount of alcohol in her blood she could have been charged with causing her daughter’s death by dangerous driving had she survived.

An examination of the Toyota after the crash found no mechanical defects and that Mrs Morley had not braked before the impact.

Dr Earland ruled that Mrs Morley’s death was accidental but she had unlawfully killed her daughter.

“I am satisfied that shortly before 11.52am on October 25 2008 the car being driven by Veronica Morley, who had consumed a quantity of alcohol and diphenhydramine, went out of control on the A30 landing in a tree line,” she said. “There was no evidence of braking.

I am satisfied that on the balance of probability her death was an accident.”

Turning to Zoe, the coroner said: “I am satisfied that the car in which Zoe was a rear seat passenger went out of control on the carriageway and went into a tree line.

“There was no evidence of braking and alcohol and diphenhydramine were factors.

“And coming to my conclusion I am satisfied beyond reasonable doubt that the car accident was caused by the consumption of unlawful and dangerous levels of alcohol, which inadvertently caused death.

“I am satisfied that a reasonable and sober person would realise that Zoe would have been at risk of unintentional manslaughter and so my verdict is unlawful killing.”

Mrs Morley’s former husband, David Morley, who was present in court left the inquest without commenting.