In the vexed media firestorm that preceded the real trial, Hey Dad star Robert Hughes (pictured), convicted this week of sexually assaulting three girls in the 1980s, was painted as a monster before he ever took the stand, his lawyer Greg Walsh argues. Questions of prejudicial coverage and its effect on juries are going to be a key plank of the appeal.

Walsh has plenty of material. He told Crikey he spent months researching the coverage, filing “six or seven” volumes of it to the New South Wales Supreme Court. He’s concerned with much that was reported before his client was charged, and what happened during the trial.

Justice Peter Zahra shot down many of Walsh’s requests for the charges to be dismissed on grounds of prejudicial coverage. But he did say he would refer Mamamia to the Attorney-General’s Department over a piece published on March 6 (during the trial) that made comments like: “Hughes has not been convicted … yet” and “Hughes moonlighted as a sexual predator”.

Media ethicist Denis Muller, when alerted to the contents of the Mamamia article (since taken down), says it’s one of the most shockingly prejudicial pieces of reporting he’s seen in recent years. But it’s far from the only one on Walsh’s list.

Before the media forced the police to act, there were plenty of rumours about Hughes. In 2010, Woman’s Day broke the story, carrying allegations of the abuse by Hey Dad cast member Sarah Monahan in 2010. That original story didn’t name Hughes but said the abuser had been involved with the show. Editor-in-chief Fiona Connolly says this was done on legal advice, and because the magazine didn’t want to prejudice the legal process.

“We didn’t go into that story lightly,” she told Crikey. “Sarah Monahan didn’t land on our lap. We checked her story for several months before we ran with it … And because she told her story, a great deal of good came of it … Other victims came forward, and without that Robert Hughes would never have been convicted. ”

When the original story was published, it unleashed a flood. A Current Affair‘s coverage, which named Hughes a few days after the Woman’s Day story, tracked him down in Singapore, knocking on his car window to extract a denial (a surefire way to make anyone look guilty). ACA also unearthed several more victims and did much to keep the story alive, even though rival Today Tonight wouldn’t touch it.

The stories were highly publicised — but does that mean the media did the wrong thing?

Speaking generally, Mueller doesn’t think so. Victims of sexual offences are often in a powerless position, he says. The media can act as an important alternative to standard police investigations. “If victims felt able to go to the media but not to the police at first, well, then they’ve been given an opportunity for justice they might not have had otherwise,” he said.

And anyway, giving the rich and famous a free pass because they’re rich and famous is hardly fair, adds the University of Melbourne’s Jacqueline Horan — an expert on juries.

“[The jury] would have seen the reports. The Daily Telegraph called him a heinous paedophile.”

It’s not the first time the media has opened up a case of this type. In 2001, Andrew Rule, then writing in The Age, bought to light allegations of sexual abuse committed by then-Aboriginal and Torres Strait Islander Commission chair Geoff Clark. His narrative-driven expose, vigorously defended by then-editor Michael Gawenda, was controversial at the time. After significant care was taken in checking the women’s stories, the final pieces covered the allegations as fact rather than just one side of a story, leading to fears it made it impossible for Clark to get a fair trial. Six years later, one of the women won a civil case against Clark.

Sometimes trials are moved or not held in front of juries entirely for fear of prejudice. But generally speaking, the legal system operates on the principle that juries can put aside everything they’ve read prior to the trial starting, even though some experts say this is practically impossible. Walsh argues Hughes’ jury was prejudiced before they ever entered the courtroom.

Will this play in the appeal? One legal expert Crikey spoke to, who declined to be named, was sceptical, but Horan says the way such media coverage is treated varies greatly between judges and jurisdictions. “The basic case law is that it has to be extreme prejudice,” she said. But with the internet making damaging coverage easier than ever to access — and harder to cordon off geographically — it’s not clear what this means now.

David Rolph, an associate professor at the University of Sydney, says the tone of the coverage changed when Hughes was charged, and again when he was convicted. “Arrest and charge is the bright red line,” he told Crikey.

“The legal system tries to strike a balance between freedom of the press and the right to a fair trial. It treats arrest and charge as the defining moment. Of course, the media can write lots of prejudicial stuff before that, subject to the laws of defamation. But if you constrain the media before the charge, what if a person is never arrested?”

Walsh concedes the media has a role to play in cases like this. But he argues it’s a matter of degree. In this case, he says the reporting was so prejudicial and so overwhelming that there was no way Hughes could have got a fair trial.

“The media have a job to do, and it’s a fundamentally important one,” he said. “I’m not trying to blame the media per se. But [the jury] would have seen the reports. The Daily Telegraph called him a heinous paedophile.”

Faced with this, Walsh says, there’s no way the jury were impartial when they went into the case. It’s the argument he made last time, and he’ll make it again in his appeal.