Bruce Shillingsworth Jr, 32, was found guilty of aiding and abetting arson for his role in a fire that caused $5.2 million in damages at the historic building in December 2021.
Donning a traditional purple headdress and a kangaroo pelt, Shillingsworth was also sentenced for assaulting of frontline community service provider, property damage and obstructing a territory official in the ACT Supreme Court on Friday.
The fire at the Old Parliament House in Canberra caused millions of dollars damage. (Lukas Coch/AAP PHOTOS)
Justice David Mossop sentenced him to three years and six months good behaviour and fined him $8000 to be paid within three years for his role in the fire.
He was also fined $200 for defacing public property and $100 for assaulting a frontline officer, both to be paid within a year, and received 12 months good behaviour for obstructing a territory official.
"A fine is appropriate notwithstanding his modest financial circumstances," Justice Mossop told the court.
Shillingsworth's circumstances were taken into account, with him being the sole carer of four young children, having a limited criminal history and engaging in community service work.
He was found guilty of the offences following his help in facilitating Nicholas Reed starting the fire that grew to be 1.5 metres high on the doors of Old Parliament House.
Flames from the fire reached 1.5m high on the steps of Old Parliament House. (Lukas Coch/AAP PHOTOS)
Reed was sentenced to 23 months in prison to be suspended after eight months if he agreed to a two-year good behaviour bond after a jury found him guilty of arson in September last year.
Reed was found to have shovelled hot coals from a small fire on the steps of Old Parliament House to the portico and gathered and brought back numerous bundles of sticks.
"(Shillingworth's) culpability is significant but less than that of the principal offender," Justice Mossop said during sentencing on Friday.
Shillingsworth was found to have instructed protesters to paint over CCTV cameras and create a line of people linking arms to block officials from putting out the fire.
He was also found guilty of pushing a police officer.
"The assault was a very minor one, lasting only a very short period of time, it's of a low range of objective seriousness," Justice Mossop said.
Old Parliament House required extensive repairs after the blaze. (Lukas Coch/AAP PHOTOS)
The Indigenous activist saw Old Parliament House as a "legitimate target" and indicated going through the doors would be symbolic of taking on the Australian government for grievances over First Nations treatment, the court heard.
Shillingsworth argued it wasn't his intention to burn down the doors or harm frontline staff, although Justice Mossop said he expressed little remorse for the damage.
If he was incarcerated, the cycle of inter-generational trauma would begin for his four children and result in "more anger and frustration towards the system", Shillingsworth argued ahead of sentencing.
Restitution for the damage was no longer sought, as there was no capacity for it to be paid, the court was told.
