At Christchurch District Court today, Mason represented himself at a judge-alone trial on a charge of failing to report to his probation officer "on a number occasions" at Corrections' Annex Rd office in Christchurch between January 11 and May 28 last year.
Mason gave 17 dates that he says he reported, but Corrections had looked at its records and found no evidence to back up those claims.
Four warning letters over his failing to report were issued to Mason, and Corrections had "tried to engage" with him to try and resolve the issue without it heading to court, Crown prosecutor Dr Heather McKenzie said.
At the outset of today's trial, Mason said he had "refused" disclosure, claiming it had "been through 11 separate sets of hands, which surely must breach some kind of confidentiality act".
"Well, that's your problem, not mine," Judge David Saunders said.
Corrections staff gave evidence that Mason failed to report for community work on several days as required.
Under cross-examination by Dr McKenzie, Mason admitted not reporting on any of those days.
Mason believed he had completed his community work hours, despite Corrections records saying he had more than 90 hours to go.
Under questioning by Judge Saunders, Mason accepted Corrections never told him he had completed his hours.
Judge Saunders concluded that Mason did not have a reasonable excuse for failing to do his community work.
Mason will now be sentenced on April 29.
Canterbury builder Craig O'Neill, 39, and his carpet layer nephew Dylan O'Neill, 22, have since admitted assaulting Ryder outside a Merivale bar on March 28, 2013.
They will be sentenced on May 6.
