Brendan Russell Sinclair shifted the blame to an ex-lover and tried to argue his solicitor gave him the impression he had to plead guilty or risk dying in goal.

But Chief Justice Terence Higgins said Sinclair had received good legal advice, and described the move as a bid by the ill man to avoid the prospect of jail time.

Sinclair began contacting the victim, a 14-year-old boy, in 2007 through an SMS social networking group. The 43-year-old allegedly sent the boy explicit sexual text messages.

The boy's mother discovered the texts and called police, who started posing online as the victim.

The Commonwealth prosecution against Sinclair has dragged on since his arrest and extradition to the territory in July 2007.

Sinclair initially pleaded not guilty and had been due to stand trial in May 2009 before pleading guilty at the last minute.

He admitted using a carriage service to transmit indecent material to a person younger than 16, intending to make it easier to procure the recipient to engage in sexual activity.

But in a 2010 sentencing hearing in the Supreme Court, an emotional Sinclair sacked his legal team, solicitor Steven Stubbs and barrister Bernadette Boss.

The defendant argued he never intended to engage in sexual intercourse with the teen, and blamed his then partner ''Nick'' for the correspondence. And in June last year, Sinclair applied for leave to withdraw his plea.

The man said Mr Stubbs told him: ''The evidence is stacked against you. You only have two choices, (a) to die in jail or (b) to plead guilty and with mitigating circumstances you will get a suspended sentence allowing you to die at home.''

The defendant said he'd never intended to have sex with the boy but said he was ''30 per cent'' responsible, and ''Nick'' 70 per cent.