The President of Chechnya should be called to give evidence in the Anna Politkovskaya murder trial, one of her lawyers said today.

Ramzan Kadyrov should answer questions in the case against four men accused of involvement in the killing of the campaigning journalist, Karinna Moskalenko, who represents Ms Politkovskaya's family, said.

She said that Chechnya's feared strongman had not been questioned by investigators although he was repeatedly mentioned in case files and witness accounts. Ms Moskalenko added that Mr Kadyrov had "threatened Politkovskaya".

Ms Politkovskaya repeatedly criticised the Chechen leader in her reports for Novaya Gazeta newspaper and accused militias loyal to him of carrying out acts of torture.

"Questioning him is important to the case," said Ms Moskalenko. "The investigators also ignored the fact that the murder took place on Vladimir Putin's birthday."

The demand came after Moscow District Military Court ruled at the opening of the trial that the case against the defendants should be heard in public. Judge Yevgeny Zubov rejected prosecution arguments that the case should be heard in secret because one of the accused is a former agent with the Federal Security Service (FSB), the successor to the Soviet Union's KGB.

The decision was a surprise victory for the Politkovskaya family, who had been pressing for an open trial. Military courts normally hear cases in secret because they are presumed to involve sensitive material.

"I did not expect that this decision would be taken. With this judge there is the chance of a fair trial," Ms Moskalenko told reporters.

The former FSB officer Pavel Ryaguzov is said to have provided the journalist's home address to her alleged assassin. That man, Rustam Makhmudov, is not on trial, however.

He has disappeared since being accused of killing Politkovskaya and investigators believe that he has fled the country. Two of his brothers, Dzhabrail and Ibragim Makhmudov, are on trial, accused of tracking Ms Politkvoskaya's movements in the two weeks before she was gunned down in the lobby of her apartment building in Moscow.

The fourth defendant is Sergei Khadzhikurbanov, a former investigator with the organised crime unit of Moscow police. All four have denied the charges.

Investigators have still failed to identify who might have ordered the journalist to be killed and why. Defence lawyer Murad Mussayev dismissed the case as a trial of "two drivers and a go-between".

He said: "We want the world to see that the goal of this trial is to show that a major crime has been solved when that is not true."

Ms Politkovskaya was shot on Vladimir Putin's 54th birthday in October 2006, sparking international outrage and fears that critics of the Kremlin were being silenced. Mr Putin, who was then President, initially remained silent but pledged days later that the killers would be caught, calling the journalist's death "an unacceptable crime that cannot go unpunished."

Ms Politkovskaya, who was 48, was a fierce critic of Mr Putin, particularly over the conduct of the war in Chechnya. She catalogued abuses committed by Russian forces and by private militias loyal by Mr Kadyrov.

In a radio interview two days before she died, Ms Politkovskaya implicated a group controlled by Mr Kadyrov in killings. She said: "I am conducting an investigation about torture today in Kadyrov's prisons. These are people who were abducted by Kadyrovsty for completely inexplicable reasons and who died."

Her final article in Novaya Gazeta was incomplete but detailed evidence of torture on civilians by police in Chechnya, including stills from a video showing assaults on two unidentified victims. The published material did not link Mr Kadyrov directly to the allegations, however, and he has repeatedly denied any involvement in her death.

Times Recommends

• 'New York has lost its edge'
• Copenhagen will fail – and quite right too
• More than 17,000 new underwater species found