Joshua Josef Barker, of Kings Meadows, has pleaded not guilty to murdering Mr Watson during an alleged hit-run on March 9 last year and assaulting Timothy John Bumford shortly after.

The Launceston Supreme Court jury were on Thursday shown photos from the scene, as well as a sketched reenactment of the ute's path, created as part of the police investigation.

While giving evidence, Tasmania Police Senior Constable Michael Rybka said there was no evidence to suggest Mr Barker's ute was out of control when it mounted a kerb on the corner of Knox and Burrows streets and hit Mr Watson at a speed between 40km/h and 47km/h.

The court was told there were two impacts on the bonnet of the ute from the alleged incident, with the more substantial dent likely to be from Mr Watson's hand after his arm swung around the side of his body, into the air and collided with the bonnet.

Senior Constable Rybka said the car was driven quite skillfully, avoiding an Aurora pole and narrowly missing a car parked on a nature strip.

"The vehicle had to be under acceleration to complete the turn," he said.

There was only a split second between the ute hitting the gutter and Mr Watson, the court heard.

Senior Constable Rybka said an ordinary person wouldn't have time to first perceive the ute and then react to it.

Defence lawyer Evan Hughes will cross-examine Senior Constable Rybka after lunch.

The trial before Justice Robert Pearce continues.