He then indecently assaulted the woman and ran from the scene.

The victim chased after the man, who hid behind a shopping trolley.

As the victim approached Collyer, he pushed the shopping trolley toward her and caused her to fall to the ground.

The man was detained by security until police arrived.

Collyer’s lawyer Clare Hay told the court her client did not remember the assaults.

“Mr Collyer doesn’t recall this incident,” she said.

“He remembers being held by security but nothing else.

“He said he finds himself a disgrace … he’s ashamed and he’s remorseful.”

Ms Hay acknowledged that a term of imprisonment would be appropriate but asked Mandurah Magistrate Anne Longden to consider a suspended sentence.

Senior Constable Read opposed a suspended sentence, saying she was worried about the “opportunistic nature of the offending” and Collyer’s “threat to the public”.

Ms Longden agreed the case was “disturbing” and “simply too serious”.

“This isn’t your first [time] sexual offending,” she said.

“You were dealt with some time ago for what I would call like offences.

“This was no doubt a very frightening incident for the victim who was just going about her business.”

Ms Longden described the assault as “sinister”.

“You followed her into a confined space,” she said.

“The risk of future like behaviour is well above.”

Collyer was sentenced to 14 months imprisonment for unlawful and indecent assault and four months imprisonment for common assault, backdated to October 27 when he was remanded in custody.

He was made eligible for parole.