Convicted doesn't mean he did it. If he had been acquitted I'm sure there would be tons of people arguing that the jury got it wrong.
You skipped over the part of my post where I establish that Pell's lawyer thinks Pell did it. That Pell was seized by an irresistible impulse upon seeing the boy and penetrated the boy's anus in a somewhat unremarkable manner. You can't understand why everyone is making such a fuss about it; the boy had clearly been placed there by the devil to tempt Pell, and deserved to be taught a lesson.
Here we have a Cardinal of the Roman Church, a member of an elite group of God's own representatives on Earth, anointed in holy oils and dressed up in holy robes. Buggering young boys entrusted to his care. Pell's conviction is a start but there are thousands more like him. Going about their lives, hiding in plain sight, secure in the knowledge that the Church will never turn them in. And who can blame the priests when their lord and master does the same thing - stand by and do nothing, or heap violence and death on innocent children.
Richter uses mitigating 'arguendo' pleas solely to reduce the penalty. It is standard practice.
If he had asked for sentencing leniency on the grounds that Pell was (still) innocent, guess what the Judge would have said.
The mitigating argument being that Pell has always been attracted to young boys, and that on the day in question he was overcome by lust and his desire to stick his engorged penis into said boy's anus, and he proceeded to do just that? Are you fucking kidding me? You plead for leniency by arguing that Pell had devoted his life to the service of the church and the community, by parading in witnesses to testify to his character and good works, and so on. Pell confessed to the crime after he had been convicted; no innocent man in his position would confess to being a pedophile, ruining whatever remained of their dignity and legacy, just to get their prison sentence reduced by a few years. They would die in prison proclaiming their innocence to the last breath. Pell is not just a convicted criminal, he is also a pussy, lacking integrity and loyalty to his employer, his family and the community he claimed to have served, willing to sell out his church, and bring shame on everyone associated with him by confessing his guilt just to get a lighter sentence.
I am certain you understand why your statements are absurd. If Pell had been captured on video in the act of planting his penis into the boy's anus, you would still be proclaiming his innocence, making up some equally absurd claim about how the boy had tempted and seduced Pell just to make the Roman Church look bad.