Shane Van Duren, 43, was handed a suspended prison sentence of two years and six months' and ordered to serve 200 hours community service after a desperate struggle to free his beloved Belgian shepherd, Kalu, turned violent in 2015.

His sentencing judge described the close relationship between Van Duren and the therapy dog as "a type of dependence" that treated his ongoing post-traumatic stress disorder and helped heal psychological wounds suffered in East Timor.

Van Duren sliced through three wire fences to let the dog out of the RSPCA's Weston headquarters, before he fled with the animal, one night in December.

Kalu had been seized and taken to the shelter after a member of the public found it wandering the streets looking "thin", court documents said.

Van Duren posted on his Facebook page the day after the break-out, saying he hadn't seen the dog since it went missing more than a week earlier.

"Today after a recon [sic] of the RSPCA I found him locked up in the back kennel and sprung him," Van Duren wrote.

Two police and two RSPCA inspectors went into his Deakin home the next day, but Van Duren refused to surrender the animal as he was arrested and yelled: "You're not getting my dog."

When the police officer tried to subdue him by grabbing the offender's arm and attempting to pull him to the ground, Van Duren punched him in the face before he put him in a headlock.

The second police officer handed the nearby RSPCA inspector a can of OC spray, prompting Van Duren to strangle the woman with one hand as he tried to get hold of the can.

The officer struck Van Duren's knees repeatedly with a baton until his legs buckled and he yelled at the inspector: "You're f---ing dead bitch, this is only 50 per cent of what I can do."

Van Duren was later charged and spent 46 days in custody.

He pleaded guilty to assault and strangulation the day his ACT Supreme Court trial was set to start in April.

Defence lawyer Louise Taylor said on Thursday while it was easy to step back and say Van Duren should not have taken the law into his own hands in such a violent way, his actions were driven by his sense of injustice at the dog being seized.

While that motivation didn't excuse his actions, it went some way to explaining why he lashed out, she said.

He also maintained he'd been unfairly targeted by the RSPCA, which had previously seized another dog from his backyard that was being nursed back to health.

"He felt quite desperate at the prospect of Kalu being seized and the prospect of living without the dog on a daily basis," she said.

Ms Taylor said Van Duren had apologised and complied with police after he lashed out at the inspector.

"He accepts it would have been a very scary incident for her and she would have been fearful throughout it."

She said the dog had been returned to Van Duren last month "to the delight of my client and his family".

Prosecutor Anthony Williamson said the incident was serious and the woman was attacked in her line of work and by a trained soldier.

He said the choking caused the inspector's face to go deep red, she struggled to breathe and felt she would black out or die.

She'd suffered bruising to her neck, while the police officer's bleeding ear required a stitch.

Chief Justice Helen Murrell said incident must have been "terrifying" for the inspector.

She noted Van Duren, a former soldier, was confronted with many traumatic situations that included the death of personnel in East Timor in 1999 and 2000.

Ms Murrell said that trauma undoubtedly continued to have a significant psychological impact on Van Duren and accepted time behind bars could worsen his condition.

She said Van Duren, who had the support of the veterans' community, "benefited greatly" from the dog's company and found the animal therapeutic.

Van Duren was ordered to serve a good behaviour order for the length of his suspended sentence.

He was also fined $200 for trespass and ordered to serve a six-month good behaviour order for damage to the RSPCA site.