The Ballarat jury found Graham Bruce Collins guilty of three counts of indecent act with a child under 16 and one count of sexual penetration of a child under 16.

The jury acquitted Collins on four counts of indecent act of a child under 16.

The offences occurred in 2015 and 2016 when Collins was 75-years-of-age.

At a plea hearing at the County Court in Ballarat on Friday, defence barrister Jacob Kantor said Collins was a person of good character, having been mayor three times.

He said Collins had received a fire services medal and was nominated for continued and distinguished services to the community.

Mr Kantor urged the court to consider Collins' consistent work history and excellent family support in sentencing.

He said Collins had no criminal history and was unlikely to reoffend.

Mr Kantor said a jail sentence would be more burdensome.

The prosecution highlighted the seriousness of the charges and called for an immediate jail sentence.

Prosecutor Pat Bourke said Collins became a serious sex offender after the second offence.

Judge James Montgomery said Collins was facing a jail sentence.

He said Collins did not admit the offences ever occurred and he would sentence him on the jury verdict.

"At this age he is facing a jail sentence," Judge Montgomery said.

"His wife and children would no doubt be grappling with the conviction and what it says about his character."

The plea hearing was adjourned for the defence to gather Collins' medical history.

Collins will be sentenced in Melbourne at a date to be fixed.