Verdicts loom in NCA bombing case

The 1994 bombing killed Detective Sergeant Geoffrey Bowen and seriously injured lawyer Peter Wallis.

Sgt Bowen died from horrific injuries, including the loss of his left arm, while Mr Wallis lost an eye and suffered severe burns.

Perre pleaded not guilty to the murder of Sgt Bowen and the attempted murder of Mr Wallis.

The 64-year-old elected not to give evidence but his defence team said the investigation into the bombing was plagued by tunnel vision.

Lead counsel Gilbert Aitken told the court that in the eyes of SA detectives only Perre had the motive to make and send the bomb.

"This tunnel vision resulted in investigating officers becoming so focused on one individual, namely Mr Perre, such that no other person or persons ever truly registered in the investigators' thoughts," he said.

"This investigation took a wrong turn at its inception."

On the crown case, the bombing was a personal attack on Sgt Bowen.

Prosecutors said Perre's hostility towards him had grown because of their interactions following the seizure of a multi-million dollar cannabis crop in the Northern Territory in August 1993.

While a number of people had been arrested, Perre was also suspected of being involved and was targeted by police and Sgt Bowen, who had been seconded to the NCA.

In her opening, lead prosecutor Sandi McDonald SC said at the time of his death, almost all of the officer's work had involved the drug crop with the accused being a principal target.

"It is the prosecution case that it was no accident that Geoffrey Bowen died as a result of this bomb detonating. He was the intended target," Ms McDonald said.

But Mr Aitken told the court that Sgt Bowen had also crossed swords with other people in relation to different investigations and accused a number of key prosecution witnesses in the case of lying.

The defence also argued that there was no forensic evidence to directly link Perre to the bomb.