At the same time, Dr Tomison said he grew defensive at the growing gap between what he saw as his morals and the system he was presiding over.
It resulted in what he said was too much faith being placed in those beneath him.
Dr Tomison said it was for that reason he signed a briefing note to the Corrective Services Minister, prepared by his staff, which he acknowledged in hindsight contained “grievous lies” about what conditions in Unit 18 would be like.
“Clearly I should have looked into it more intensively … clearly I’ve failed on a level of not doing more due diligence,” he told the court.
His evidence has been so astounding that lawyers from the State Solicitors Office, who represent the Department of Justice and Dr Tomison, have been trying to clarify some of what he said.
“When you said you were stuck between a rock and a hard place, what did you mean by the terms a ‘rock’ and a ‘hard place’?” was one question put to him.
Coroner Urquhart warned they seemed to be questioning the honesty of some of the former Director General’s answers.
Crisis a decade in the making
But the crisis which Dr Tomison says contributed to some of those decisions did not materialise overnight. It was more than a decade in the making and partially under his watch.
Over those years the main detention centre at Banksia Hill went from a world-class facility to one where heavily armed officers were aiming weapons at the heads of teenagers after a riot last year.
At countless points, including before Tomison took the helm in mid-2017, decisions were made which did not stop that descent into chaos.
A crucial moment for many is late 2012 when, without even completing a risk assessment, the government moved young people serving out their sentence and those waiting for their next court date into the one facility.
Within months, jamming them all together contributed to a riot so damaging more than 70 young people had to be moved to Hakea adult prison because there weren’t any safe cells left at Banksia.