The crash which killed a Stroud brother and sister was caused by a faulty tyre and lowered suspension, an inquest heard today.

Bobby Roberts’ 2.8 litre Volkswagen Golf V6 veered sharply across the A419 Ebley bypass, collided with an oncoming vehicle and crashed upside down in to a ditch. He and his sister Jinny-Mae Cook were killed instantly, the Gloucester inquest heard. Another passenger, Nick Gayle, survived.

Tests after the crash on November 15, 2014, later found dad-of-one Mr Roberts, 28, was more than two-and-a-half times the drink drive limit and had traces of cocaine in his blood.

However Coroner David Dooley concluded that the offside front tyre probably deflated so rapidly that it could not be known whether the alcohol, drugs and loud music in the car would have made for a different outcome. The inquest heard that the front offside tyre and both rear tyres were under the 1.6mm tread depth limit - and the same three were too also too wide.

That meant that there was not enough space between the offside front tyre and the lowered suspension strut, and the two rubbed. There was so little tread on that tyre that the metal cord was showing, and the front suspension damper had an oil leak, police investigator Peter Davies said.

“The front offside suspension strut being lowered intentionally or not reduced the clearance in the wheel arch,” said Mr Davies in a statement. “The offside front suspension being inoperative due to oil loss produced a problem with handling and suspension. Evidence the left side front tyre rubbed on the strut was found and could have caused the failure. A combination of poor maintenance and fitting wheels and tyres without taking in to consideration the clearance may have caused the tyre to fail.”

Hairdresser Jinny-Mae, 18, was found at the side of the car but police were not able to tell whether anyone in the VW was wearing seatbelts. Andrew Smith, who was heading the other way toward Stonehouse when Bobby’s car hit his Vauxhall Vectra, said in a statement he saw a car accelerate in to a gap, before a screech of tyres.

“It appeared the driver had lost control and I tried to avoid it,” Mr Smith, who suffered rib and ankle injuries, said. “I got out. The collision turn my vehicle 45 degrees to the left. I did not know where vehicle one (the VW Golf) was. It was upside down in a ditch facing back in the direction from where it had come. I became aware of loud music emanating from it.”

He said passing motorists stopped and he found a man lying on the ground, who it was initially believed had been a pedestrian struck by his car - however it was later confirmed he was a passenger in the Golf.

“I detected a strong smell of alcohol,” said Mr Smith. “He was talking. He was not rational or coherent and said ‘Leave me alone, I just want to go go home now.’

“I was approached by a female who said ‘I cannot believe he survived in that car.’”

Another driver, Donna Williams, saw Mr Roberts’ car suddenly veer across the road behind her, consistent with Mr Smith’s statement.

The largest tyre width for that VW Golf is 225mm, the inquest heard. But the three faulty tyres were 255mm, while the nearside front was 215mm. Mr Gayle refused to give a statement to police.

Mr Roberts and his sister were pronounced dead at the scene and Mr Dooley said post mortem examinations found injuries consistent with being killed instantly. Neither would have suffered, he said.

A toxicology report showed Mr Roberts had 210 milligrammes of alcohol in 100 millilitres of blood. The legal limit is 80mg. Another test showed 256mg of alcohol in 100 millilitres of urine. The legal limit is 107mg and the report said that second reading indicated that he had been drinking in a session for ‘quite a long period’ beforehand. The report also suggested he had taken cocaine in the 24 hours before the crash.

In conclusion Coroner David Dooley said: “We have heard the car was poorly maintained. It had incorrect tyres on it and incorrect sized wheels.

“There was rubbing of the strut with the offside front tyre, which on balance of probabilities may have caused it to deflate. The tyres were in poor condition.

“The fact he was drinking to excess has to be taken in to account but there is no guarantee this accident could have been avoided if he had not been drinking at all.”

He recorded conclusions of death by road traffic collision for both.