An arsonist involved in lighting a fire that caused millions of dollars worth of damage to Old Parliament House has told a court his actions "weren't honourable".
Nicholas Malcolm Reed took to the stand in the ACT Supreme Court on Thursday, saying the blaze "went directly against the principles we were there to outline. [That is] original law, tribal law on this continent".
Reed, 32, was found guilty of arson by a jury during a trial in September. Co-offender Bruce Shillingsworth jnr was found guilty of aiding and abetting arson.
The pair were involved in the December 2021 blaze that caused $5.3 million worth of damage to the historic Canberra building during a series of anti-government protests.
Giving evidence on Thursday, Reed told the court his actions "caused a lot of harm" to the Indigenous sovereignty movement.
"In particular, in the way it has been looked on and the perception afterwards damaging a lot of work a lot of people have done for a long while," he said.
Prosecutor Soraya Saikal-Skea said the fire caused "significant" damage to the building and "detracted from the very cause the protesters are seeking to advance".
She agreed with a suggestion by Justice David Mossop that the damage to the door was intentional but the damage to the rest of the building was reckless.
"You also can't ignore the fact that the reason why [the protests were] there was because of the special status of that building," Justice Mossop said.
Reed's barrister, James Sabharwal, urged the court to consider a suspended sentence for his client.
Mr Sabharwal said Reed had demonstrated insight, remorse and "has been isolating himself in fear of public criticism".
During the trial the prosecution alleged Reed carried hot coals and sticks from a nearby smoking ceremony before placing them near the portico doors of Old Parliament House.
Ms Saikal-Skea claimed that, as "smoke starts to billow from the area of the front doors", Shillingsworth could be seen gesturing for protesters to form a "horseshoe" around the fire.
"The doors were obscured by the bodies of protesters," she said.
"A group of protesters and police clashed at the steps."
Police retreated and the "fire eventually engulfed the portico area", which caused "extensive damage", Ms Saikal-Skea said.
Justice Mossop is set to hand down Reed's sentence next week.
Shillingsworth will be sentenced at a later date.
