Jakarta – The lawyer of Pollycarpus Budihari Priyanto, the man convicted of murdering human rights activist Munir, says the Supreme Court was wrong to hear an appeal filed by prosecutors in his client's case.

"The Criminal Code strictly stipulates that only the defendant and her or his heirs have the right to file a case review petition. Thus by all means the Supreme Court justices should have ignored the prosecutors' attempt from the very beginning," lawyer Muhammad Assegaf said on Tuesday as quoted by kompas.com.

Muhammad alleged that Bagir Manan, then the Supreme Court's chief justice, had questionable motivations in approving the case review. "That is why we are picking up on the momentum today, since Bagir Manan is no longer chief, to file the case review petition," he said.

The current case review asked the Supreme Court to reconsider its previous ruling sentencing Pollycarpus to 20 years' imprisonment for premeditated murder.

Pollycarpus was initially sentenced to 14 years imprisonment by the Central Jakarta District Court for murdering Munir using arsenic poison. The Supreme Court later overturned the verdict, finding Pollycarpus guilty of only falsifying documents and reducing his sentence to two years' imprisonment.

The Attorney General's Office (AGO) then asked the Supreme Court to review its decision, which the court did in 2008, eventually finding the former pilot guilty of premeditated murder and again sentencing him to 20 years' imprisonment.

Critics have alleged that the case review of was part of plot to exonerate the people responsible for the death of Munir, who died aboard a Garuda Indonesia flight en route to Amsterdam in 2004.