Peter Cuzner, 61, is on trial in the ACT Supreme Court this week charged with two counts of indecent assault. Prosecutors allege Mr Cuzner had touched the year 9 boy's groin on two occasions while purporting to look for a pulse.

The former student took the stand for a second day on Monday, where he defended his account of the alleged assaults under cross-examination by defence barrister John Masters.

Conceding his memory may have faded over time, the witness said, "but some things that happen in your life stick vividly in your mind, and are never going to be erased".

The witness has told the court that twice in one year, first after they had gone for a drive and parked in an empty car park at the old Canberry Fair, and another after he helped the teacher with the garden at his home, Mr Cuzner had touched him near the groin.

Mr Masters questioned the witness on inconsistencies between the accounts given to police in two interviews, one in 2015 and another in 2017, and his evidence-in-chief last Friday.

In the 2015 interview, police had asked the man about the first thing he recalled about Mr Cuzner. The witness had said it was that Mr Cuzner was his year co-ordinator in year 10.

The teacher was in fact the boy's year co-ordinator in year 9.

Mr Masters suggested the former student may have "transposed" Mr Cuzner, either accidentally or otherwise, and his attacker.

The witness denied the suggestion. He said it was meant to be year 9, and things had become clearer after he saw documents, including school reports, when shown by police during a later interview in January 2017.

The witness agreed he had not told police Mr Cuzner had also checked his neck for a pulse, though that had emerged on Friday and he stood by the claim. In one police interview, the witness had said he himself had undone Mr Cuzner's belt when they were in the car, but told the court on Monday that was wrong.

Questioned by Mr Masters on the apparent inconsistencies, the witness told the court he found the topic difficult to talk about.

Also in the August 2015 police interview, the witness had said a 1980s yearbook photo of Mr Cuzner,"didn't look like him". The witness later clarified his comments, saying it was a bad photo.

In the same police interview, the court heard, the witness had described Mr Cuzner as "just a pastel-wearing cool kid wannabe".

You didn't have a high regard for Mr Cuzner? Mr Masters said.

"I didn't dislike him more than any other teacher," the witness replied. "I didn't have a special hatred for him, no."

It also emerged on Monday during cross-examination that before the witness had spoken to police, he had sought the advice of a lawyer. That lawyer had written a letter to Catholic authorities.

The witness said he was going to initiate a civil case in relation to the alleged abuse by Mr Cuzner. He said he had never made a complaint to police about the alleged abuse.

The trial continues before Chief Justice Helen Murrell.