Former Hey Dad! star Robert Hughes had boiling water thrown at him while in protective custody at Goulburn jail, an appeal hearing against his conviction has heard.

On Tuesday the Court of Criminal Appeal heard Hughes had been targeted by other inmates in prison despite being held in segregation in the maximum-security correctional centre.

Hughes is serving a non-parole period of six years, with a maximum term of 10 years, for 10 counts of sexual and indecent assault on four young girls in the 1980s and 1990s.

On the second day of his appeal hearing, Crown Prosecutor Nicole Noman SC told the court: "It's not challenged that a number of unfortunate incidents happened."

Justice Monika Schmidt said: "Including having boiling water thrown [at him], which seems extraordinary in the custodial environment we're discussing."

Hughes is appealing his conviction on 10 grounds, including that the trial judge was wrong to refuse an application to permanently stay the proceedings and to refuse to order separate trials for each complainant.

Hughes' barrister, Phillip Boulten, SC, says the trial miscarried in part because of pre-trial publicity and commentary on social media.

Mr Boulten also detailed the history of one of the complainants in the Hughes trial giving paid media interviews in 2010.

The court heard the woman and another prosecution witness gave interviews to Channel Nine's A Current Affair and to Woman's Day magazine in a publicity deal organised by agent Steve Moriarty.

"This is the only case I have ever seen where the complainant was paid $100,000 to go on TV and make these allegations before they went to the police," Mr Boulten said.

The woman had used the broadcast to "call out" to other potential complainants.

He said publicity surrounding a criminal investigation into Hughes continued until he was extradited from Britain and charged. It then continued throughout the trial.

The numerous social media posts, including YouTube videos, "were designed to vilify; to make him a pariah".

Hughes was found guilty by a District Court jury in April 2014. In sentencing Hughes, Judge Peter Zahra described the popular sitcom actor as a sexual predator who systematically exploited young girls and then relied on his position to ensure his victims' compliance and silence.

Hughes, who remains in Goulburn jail, did not appear in court for his appeal and did not wish to be on audio-visual link.

The appeal continues before Justice Margaret Beazley, Justice Schmidt and Justice Richard Button.