A man accused of killing a teenager by running him down as he rode a stolen motorcycle in WA's Goldfields region told police he was chasing the boy but didn't mean to drive over him, a court has heard.

The man, who cannot be named for legal reasons, was aged 55 in August last year when he was charged with manslaughter over the death of 14-year-old Elijah Doughty in Boulder, near Kalgoorlie.

The Supreme Court of WA heard on Monday the man saw the boy riding one of two motorbikes that had been stolen from a container outside his house the day earlier, gave chase and was too close when the teen suddenly turned in front of his ute.

The family of Elijah Doughty broke down in court in December when the accused man pleaded not guilty to manslaughter after an offer to plead guilty to the less charge of dangerous driving causing death was rejected by the state. 

Elijah's death on August 29, sparked tensions in his Goldfields home town with Indigenous supporters carrying signs calling for 'justice' and saying 'the lives of our kids matter'.

A violent riot erupted outside the Kalgoorlie Courthouse when the man was first due to appear in court, leaving officers injured and police cars damaged. 

The protest began peacefully, with about 200 Aboriginal people holding signs demanding justice for the 14-year-old and claiming the accused man should have been charged with murder rather than manslaughter.

But the protesters soon became unruly and began climbing over fences and police cars to get into the court complex, smashing glass doors.

Several people were arrested. 

- with Heather McNeill