A US man linked to the fatal shooting of two Queensland police officers has claimed his right to guns for self-defence has been violated by charges of alleged firearms possession while a convicted felon.
Donald Day Jr, 58, was arrested in December 2023 by the FBI in Arizona on two counts of "interstate threats" 12 months after the fatal shootings at rural Wieambilla, west of Brisbane.
He was later charged with illegally possessing firearms including three military-style rifles, handguns and a sawn-off pump-action shotgun along with a large cache of ammunition.
Day was convicted in the US state of Wyoming in 1987 of larceny, defined as a felony or serious crime, which prohibited him from using and owning firearms.
Public defender Jon Sands last week filed a defence on the firearms charges that claimed his Second Amendment rights under the US Constitution had been violated.
That amendment states "a well regulated militia, being necessary to the security of a free state, the right of the people to keep and bear arms, shall not be infringed".
Mr Sands referred to a landmark US Supreme Court decision in 2008 that found many forms of gun control violated the constitution.
"The Supreme Court held that the Second Amendment codified an individual right to possess and carry weapons, the core purpose of which is self-defence in the home," Mr Sands said.
The judges behind the 2008 decision stated at the time their ruling did not affect the ability for the US government to ban gun ownership by felons or people with a mental illness.
Queensland police in January started providing confidential evidence to the FBI concerning the killing of the two officers and a Wieambilla resident.
Constables Matthew Arnold and Rachel McCrow were shot in cold blood by Nathaniel, Gareth and Stacey Train after the officers arrived at the Wieambilla property.
Neighbour Alan Dare was also shot dead before the Trains were killed in a gunfight with specialist police later that night.
Between May 2021 and December 2022, Day, of Heber, Arizona, is accused of repeatedly sending messages about a "Christian end-of-days ideology" known as premillennialism to the Trains.
Mr Sands last week said Day should not face trial for allegedly possessing a shotgun with an illegally shortened barrel as it was similar to the type of weapons popular in the US when its Constitution was drafted in 1787.
"Many blunderbusses of the period, for instance, had barrels shorter than 18 inches," he said.
US federal prosecutors have yet to file a response to Day's motion to dismiss the two firearms charges.
Mr Sands has previously claimed prosecutors do not have sufficient evidence or legal precedents to support interstate threat charges against Day, who has been denied bail.
Day was initially charged with threatening public figures linked to the World Health Organisation's COVID-19 response and was later charged with threatening to kill FBI agents.