At last year's Dandenong-Cranbourne RSL Anzac Day parade, Colin Maurice Gibbons, 57, marched wearing seven medals and the badge and red beret of a Vietnam War military policeman.

But in reality, the closest Gibbons ever got to military service was a brief stint in the army of his native New Zealand when he was 17.

Gibbons pleaded guilty before the Dandenong Magistrates Court last Wednesday to falsely representing himself as a returned soldier, wearing service decorations not conferred on him and falsely representing himself as the person who had received those decorations.

Defence counsel Larry Gage told the court his client was ashamed and had never sought any financial advantage when posing as a war veteran.

"Really, what he got out of this was acceptance by the veteran community."

But the court heard Gibbons had a long history of dishonesty and assuming identities.

He also:

■ Claimed part of a lung he lost to cancer was due to being exposed to the Agent Orange herbicide.

■ Told visitors at the Vietnam Veterans Museum at Phillip Island about the war horrors he had witnessed.

■ Attempted to defraud Medicare in 2008.

Prosecutor Glenn Horman opposed Mr Gage's call for any jail term to be suspended.

"Vietnam veterans put their lives on the line ... and should get the respect that is entitled to them," Leading Senior Constable Horman said.

Magistrate Pauline Spencer told Gibbons that while he had expressed remorse "you betrayed a trust, a very big trust".

She sentenced Gibbons to four months' jail, of which 14 days must be served.

If he breaches a 12-month good behaviour bond, the whole sentence will apply.

Gibbons was released on bail after lodging an appeal, which is due to be heard in the County Court in May.