Bangladesh's former chief justice was sentenced in absentia to 11 years in jail for corruption on Tuesday, in a case that opposition groups and supporters say is politically motivated.

Surendra Kumar Sinha, 70, headed the Supreme Court when it ruled in 2017 that parliament could not sack judges, a move hailed by lawyers as safeguarding judicial independence.

Sinha left Bangladesh in late 2017 alleging he had been forced to step aside following the landmark ruling. He lives in North America where he has reportedly sought asylum.

Campaigners have said his departure was a massive blow to the credibility of the country's judiciary, and accused the government of going after Sinha. 

"It was very obvious that the government was angry with him and... was determined to just kill his reputation," Asif Nazrul, a law professor at Dhaka University told AFP.      

Judge Shaikh Nazmul Alam of Special Judge's Court in Dhaka delivered Tuesday's verdict, ordering Sinha to serve seven years in jail for laundering money and four years for breach of trust, prosecutor Khurshid Alam Khan said.

"This verdict proved that nobody in the country is above law. Wrongdoings will bring anyone in the trial," he told AFP.

Sinha was the first Hindu chief justice in the officially secular Muslim-majority nation of 169 million.

He later wrote a book titled "A Broken Dream: Rule of Law, Human Rights & Democracy" in which he said he had been forced to resign and flee after being threatened by a military security agency.