THREE men are responsible for the deaths of four people who were killed by a 32-tonne lorry which careered into them after its brakes failed, a court heard.

Mitzi Steady, four, Robert Parker, 59, Philip Allen, 52, and Stephen Vaughan, 34, died in Bath on February 9 last year.

Bristol Crown Court heard they were struck by the heavily loaded Scania truck carrying aggregate down Lansdown Lane in Upper Weston just after 4pm.

The vehicle's driver, Phillip Potter, 20, his boss Matthew Gordon, 30, and mechanic Peter Wood, 55, face 14 charges in connection with the incident.

Potter and Gordon, both from Dauntsey, and Wood, of Brinkworth, deny the charges against them.

Opening the case for the prosecution, Adam Vaitilingam QC told the jury of seven men and five women the defendants were "criminally responsible" for the deaths.

"On February 9 last year, a Wiltshire company called Grittenham Haulage sent two of its lorries out to pick up materials and deliver them to various building sites around the area," he said.

"The drivers were Mr Gordon and Phillip Potter. Gordon was the owner of Grittenham Haulage Limited. Potter was an inexperienced driver who worked for him.

"He had only been at the company for a few days. Although he was driving that lorry, he was in reality following after the lorry that was being driven by his boss."

Mr Vaitilingam said Potter and Gordon made four trips to Shorncote Quarry to collect aggregate, taking the weights of both lorries almost to their maximum of 32 tonnes.

Following the fourth visit to the quarry, the two "fully laden" lorries headed to their final destination of the day - the park and ride at Newbridge, close to Bath.

Gordon, followed by Potter, drove down Lansdown Lane, a long and steep hill that runs through the village of Weston.

"Gordon's lorry was in front and leading the way but as they went down the hill the brakes of Potter's lorry failed," Mr Vaitilingam said.

"His lorry continued to career down Lansdown Lane out of control. It caused absolute devastation.

"By the time it finally came to a stop, four people had suffered fatal injuries - a four-year-old girl who had been crossing the road with her grandmother, and three men who had been travelling together in the same car.

"We, the prosecution, say that they (the defendants) each carry criminal responsibility for what went wrong that day and therefore for the deaths of those people and the serious injuries too."

Potter denies causing the deaths of Mitzi, Mr Parker, Mr Allen and Mr Vaughan by dangerous driving and by careless driving.

He is also charged with causing serious injuries to Karla Brennan and Margaret Rogers - Mitzi's grandmother - by dangerous driving.

Gordon denies the manslaughter of Mitzi, Mr Parker, Mr Allen and Mr Vaughan by failing to ensure that the brakes of the truck were in a safe condition.

He is also charged with causing their deaths by dangerous driving and by careless driving, and causing serious injuries to Mrs Brennan and Mrs Rogers by dangerous driving.

Wood is accused of the manslaughter of Mitzi, Mr Parker, Mr Allen and Mr Vaughan by failing to ensure that the brakes of the truck were in a safe condition.

The trial, in front of Mr Justice Langstaff, is expected to last between three and four weeks.

The court heard Gordon was granted an operator's licence in December 2013, the first time he had run such a business.

"The evidence will show that he was not interested in doing it properly," Mr Vaitilingam said.

"His operation was a shambles from start to finish."

The jury heard the company was supposed to have a transport manager - responsible for ensuring the lorries were safe - but did not do so in the months leading up to the fatal incident.

Mr Vaitilingam said Gordon viewed this requirement as "not a necessity but a nuisance".

Wood was employed by Grittenham Haulage to inspect and help maintain the lorries, carrying out inspections every six weeks.

In police interview, he said the lorries should have been inspected every three weeks, telling officers: "Tipper lorries go through hell."

Virtually no defects were recorded in paperwork for the truck involved in the collision and its brakes were not properly tested, Mr Vaitilingam said.

The truck had 710,000km - almost 450,000 miles - on the clock at the time of the incident.

Grittenham Haulage did not carry out the recommended brake efficiency tests on the vehicle, the court heard.

"It is further evidence of a poorly run company that just didn't have a grip of what it needed to do to keep its fleet of lorries safe," Mr Vaitilingam told the jury.

The final safety check on the vehicle by Wood was in January last year, weeks before the tragedy.

"If Mr Wood did carry out a safety inspection that day it was wholly inadequate," Mr Vaitilingam said.

"On the date of the crash the lorry had serious and long standing defects with its braking system, meaning that it was and had been for some time in a dangerous condition.

"It is the prosecution's case that some of these defects were present at the date of Peter Wood's last safety inspection.

"He says that when he looked at the lorry it was in a perfectly safe condition.

"This sort of catastrophic brake failure doesn't just happen through bad luck.

"This was entirely predictable, the result of poor management and a disregard for the rules and a failure to comply with routine guidelines.

"It was, put simply, an accident waiting to happen."