A Sydney lawyer has accused New South Wales police of trying to cover up an assault on an art student.

In awarding almost $245,000 in damages to Rachel Gardiner, 37, a judge described the assault as vicious and unnecessary.

Ms Gardner and her lawyers are able to speak about the case now the state has decided it will not appeal the decision.

She says she believes the legal outcome confirms she made the right decision to launch the case, no matter how difficult the process.

"You should just try. If there has been an injustice against you, it is an injustice. It is not worth keeping quiet about, because it costs you more than it might cost them... to stay quiet," Ms Gardner told Lateline.

It was three years ago that Ms Gardner and two friends, ran for a Sydney train.

It was late at night and with trains in Sydney's south few and far and between, they decided to chance travelling without a ticket.

That decision was the start of a sequence of events that ended up with her leg being broken, and being left at a train station even further from help and home.

CCTV footage emerges on the eve of the trial

Security cameras at Cronulla station captured Ms Gardner and her friend arriving at the station and being questioned by rail transit officers.

After one of her friends scuffles with the transit officers, police are called. Senior Constable Craig Sands is the first to arrive, running down the platform.

"Rachel was standing motionless for a period of seven seconds. You can see it very clearly on the footage," lawyer Penelope Purcell said.

"There was absolutely nothing in that seven seconds that would give Constable Sands any reason to have assaulted her in the way that he did."

The security footage captured on four cameras at the station played a crucial role in determining the case.

"I was contacted by a young solicitor who had seen Rachel in hospital and she said 'Whatever you do, you have to get that footage'," Ms Purcell said.

It was not until a year later that Ms Gardner decided she was mentally and physically strong enough to launch legal action.

For months ahead of the trial, police maintained the art student was at fault.

Lawyers for the more than a dozen police and transit officers there that night, claimed she had assaulted police and they had used reasonable force.

On the eve of the trial Ms Purcell produced the security video evidence of what took place that night.

"It is my understanding that they had no idea I had this footage," Ms Purcell said.

At that point, lawyers for police sought and were granted permission to change some of their defence.

"It struck me as amazing how many of the officers involved suddenly had no independent recollection of the events depicted on the CCTV footage," Ms Purcell said.

Questions remain about officers' reporting of the incident: Purcell

Additional assault allegations were also raised against Ms Gardner, but no charges were ever laid.

"This is all because I didn't have a train ticket," she said.

Senior Constable Sands, who was filmed kicking Rachel that day, gave his version of events to court in a statement.

"I was concerned not to injure the plaintiff. I stepped across the plaintiff with my left leg and firmly planted my left foot on the ground. I pulled the plaintiff across my extended left leg so that she overbalanced. I then controlled her descent to the ground," he said.

The station's security cameras also show Ms Gardner limping away from the station being assisted by her two friends.

A group of police officers walk behind her.

Police say Ms Gardner refused their offer of an ambulance. Court transcripts state they drove her past Sutherland hospital leaving her at Sutherland railway station, which was even further away from where she lived.

"They just said, 'Go away. Off you go," Ms Gardner said.

Ms Purcell, who has welcomed the civil court's decision, says some questions remain unresolved.

She would like to know why no police officer at the station that night accurately recorded in their notebook what took place.

She says she also has serious concerns about why details of the scuffle were not logged that night into the police data base known as COPS.

"There are in relation to reporting events such as these, there are mandatory requirements for reporting in the police system, the COPS events system," she said.

New South Wales Police declined Lateline's request for an interview.

A police spokesman says Senior Constable Sands remains on normal duties pending the outcome of an investigation.