Police say Vaughan Doolette, 35, tried to pick a fight with the pair minutes before he swerved the vehicle across two lanes of traffic and ran over the boy's ankle on Monday night.

Prosecutors opposed Mr Doolette's bid for bail in the ACT Magistrates Court on Tuesday as they argued his "very serious, life-threatening conduct" carried out "brazenly and in public" posed a risk to the community.

But lawyers said Mr Doolette, also named as Vorn Doolette in court documents, denied "bits and pieces" of the statement of allegations. He denied to police he used the white Toyota HiAce to hit the boy in the alleged attack.

Mr Doolette did not enter pleas to two charges of using an offensive weapon dangerous to a person and common assault. The prosecutor indicated those charges could be upgraded.

Court documents said the two boys, both aged 17, were outside McDonalds when a man who police allege was Mr Doolette confronted them about allegedly throwing a stick in his car shortly after 11pm.

The boys argued with him for a short time before they began to walk away as Mr Doolette allegedly called them "pussy" and "weak" in an attempt to start a fight.

He got into his van in the carpark and drove off, soon spotting the two teenagers walking on the Antill Street footpath.

Court documents said Mr Doolette suddenly swerved his van across the median strip, sped across two lanes of traffic and mounted the kerb before he drove towards the teenagers.

The boys, fearing for their life, fled as the accused allegedly got out of the van and tried again to start a fight.

He got back in his van and drove at the pair again, this time hitting one of the boys who fell to the ground. The wheel of the van crushed his ankle, causing "extreme immediate pain", court documents said.

Mr Doolette allegedly sprayed an unknown substance at the boy before he got back behind the wheel and sped off as he mounted kerbs and revved his engine.

Police stopped the car in Ainslie. They noticed the accused was sweating profusely and his speech was erratic, but said alcohol and drug tests were negative.

They arrested him. Mr Doolette admitted to police he was driving the van, but denied he had driven dangerously or hit the boy, court documents said.

Paramedics suspected the boy's ankle was sprained or possibly broken.

Prosecutors said he'd been reported missing in South Australia and had told police he planned to return. The court heard Mr Doolette was homeless and lived in the car he allegedly used in the attack.

There were no signs Mr Doolette was suffering mental health problems or was under the influence of drugs or alcohol at the time, and it was "concerning" there was no explanation for his "outburst" of "violent offending", the prosecutor said.

"This is unexplainable behaviour against two young, innocent members of the public."

His Legal Aid duty lawyer said Mr Doolette previously lived in Canberra and had returned recently to build a new life.

She said he didn't intend to return interstate and was willing to report regularly to police. Mr Doolette didn't know the two alleged victims and could also comply with conditions to avoid them.

He was on the methadone program and had taken medication for mental health problems in the past he was not showing any symptoms, she said.

Magistrate Karen Fryar said the allegations were "very concerning" and Mr Doolette posed a risk to the community.

She refused bail. The case returns to court on December 5.