Andrew Ball, 27 of Ngunnawal, first came to notoriety when he sparked a massive police hunt through Canberra in late February.

Ball had stolen a car with a baby boy, named Morrison, inside.

Police shut down routes in and out of the city, and used a police helicopter as they tried to hunt him down.

The baby was eventually found safe and well on a porch in Palmerston a short time later.

But Ball was back in the ACT Magistrates Court on Monday for what prosecutor Anthony Williamson described as the "callous bashing of an elderly, vulnerable member of the community".

Ball kicked the disabled woman in the face in Civic in late 2012, months before he stole the car.

The woman has Wilson's disease, which impacts severely on her motor skills, making it difficult to walk and speak.

She was outside a newsagent near the Civic bus interchange in November, 2012, and had just put something in the bin.

She was walking backwards and accidentally tripped over a pram, prompting the baby to start crying.

The collision caused her to fall to the ground, and she said she apologised.

But the parents, Ball and his partner Jacinda Marie McKay, began swearing at her.

Ball then booted her in the face while she was on the ground.

McKay, who didn't turn up to court on Monday, threatened to hit her with a tray from the pram.

The victim said a bystander intervened, saying "enough, leave her alone".

The ageing woman's face was swollen for two weeks after the alleged attack, the court heard.

Ball denied the allegations, saying she sustained the injuries during the fall.

But Magistrate Beth Campbell found him guilty of the offence on Monday.

She also found McKay guilty of an assault charge, which was heard in her absence.

Ms Campbell sentenced Ball to eight months' imprisonment, describing the attack as unforgivable and cowardly.

A warrant has been issued for McKay's arrest, while Ball is already in custody.