Alleged NCA bomber Domenic Perre claims ‘anybody in Australia’ could have committed the crime due to lack of specific evidence

The alleged NCA bomber says his trial is a whodunit and he can’t be found guilty because of the “innumerate” list of people who wanted to kill an antagonistic cop.

Anybody “in the Commonwealth of Australia” could have carried out the NCA bombing due to the lack of direct evidence and its victim’s “antagonistic” manner, a court has heard.

Counsel for Domenic Perre have told the Supreme Court that “innumerate” people may have wanted to kill Detective Sergeant Geoffrey Bowen – including the main prosecution witness.

That is, they argue, due partly to the lack of any forensic evidence directly tying Mr Perre to either the bomb or the parcel in which it was sent on March 1, 1994.

It is also, they say, because of Detective Sergeant Bowen’s own personality – but they stress they do not seek “to denigrate his character posthumously”.

Perre looks toward the former NCA office from the roof of a multi level carpark in Pitt St. Picture: Brenton Edwards.

“If it was the case that he was the type of police officer to antagonise criminals, it opens the door to an innumerate class of possible suspects in this matter,” they say.

“The state of the evidence is that nobody within the Commonwealth of Australia as of March 1, 1994 can actually be excluded as having committed the NCA bombing.

“The essence of this case is ‘whodunit’.”

Mr Perre, 63, pleaded not guilty to murdering Detective Sergeant Bowen and attempting to murder lawyer Mr Wallis.

Prosecutors allege that, motivated by “festering hatred”, he built and sent a parcel bomb to the NCA’s Adelaide office.

Perre, left, the NCA building and parcel bomb, centre, and Detective Sergeant Geoffrey Bowen, right.

During a seven-month trial, they tendered three decades worth of forensic evidence and eyewitness accounts that, they claimed, proved Mr Perre’s guilt.

Mr Perre did not give evidence – instead, his counsel filed a 394-page document arguing prosecutors had failed to prove their case beyond reasonable doubt.

In it, they assert the bomb used “only a small amount” of high explosive and only an expert would have confidence the quantity would be sufficient to kill a person.

They say there “is no evidence” Mr Perre has that experience – unlike key prosecution witness and self-trained gunsmith Allan “Gadget” Chamberlain.

NCA bombing trial witness Allan “Gadget” Chamberlain. Picture: Morgan Sette.

Mr Chamberlain’s illegal firearms upgrade business was, they argue, at risk of exposure in early 1994 due to ongoing NCA investigations.

“In combination with his grim personal circumstances at the time, the spectre of such an investigation may have motivated him to commit the bombing,” they say.

“Put simply, anybody could have committed this crime.

“If Detective Sergeant Bowen was a police officer in the habit of upsetting those he investigated, there could be any number of people with the motive to harm him.”

Justice Kevin Nicholson will hand down his verdict on a date to be set.