The human rights lawyer wife of actor George Clooney, who is acting for one of the Al-Jazeera journalists imprisoned alongside Australian Peter Greste, says she was threatened with arrest when trying to publish a report into Egypt’s judicial system.

Amal Clooney, who compiled the report for the International Bar Association, told the Guardian she recommended Egypt’s judiciary be more independent of the government.

“When I went to launch the report, first of all they stopped us from doing it in Cairo,” the UK-based barrister said.

• In pictures: George Clooney’s wedding of the century 
• Style icons: Amal joins Jackie, Diana and Maria

“They said, ‘Does the report criticise the army, the judiciary, or the government?’ We said, ‘Well, yes’. They said, ‘Well then, you’re risking arrest’.”

Mohammed Fahmy, Mr Greste and Baher Mohammed were arrested in December 2013 after the overthrow of Islamist president Mohammed Morsi and were sentenced to between seven and 10 years in prison last June.

Earlier this week, an Egyptian court ordered a retrial for the three men but Mrs Clooney, who acts for Mr Fahmy, said it “doesn’t really mean much”.

She added the men were victims of a system where officials could hand-pick judges.

“We’ve seen the results of that in this particular case where you had a hand-picked panel led by a judge who is known for dispensing brutal verdicts. And this one is no different,” she said.