A Hindu fanatic sentenced to death for killing an Australian missionary and his two young sons has appealed against his conviction, court officials said.
On September 15, a court in the eastern Indian state of Orissa found Singh and 12 others guilty of burning to death missionary Graham Staines and his two sons in Orissa in January 1999.
A week later, Judge Mahendra Nath Pattnaik ordered Singh to the gallows because the murder case was the "rarest of the rare."
Singh's petition, filed in the Orissa high court on Friday, said investigations into the case were "biased and perfunctory" in nature.
He said there were several discrepancies in the statements of eyewitnesses and extra judicial confessions were "not true and voluntary."
Singh also alleged that witnesses were "tutored" and "influenced" while in police custody.
Staines, a 57 year-old Baptist missionary, had worked in India since 1965 treating leprosy patients.
Singh, an activist against religious conversion and radical vegetarian, lead a mob which surrounded Staines' station wagon in the remote village of Manoharpur on January 23, 1999, as the missionary and his children slept inside.
The crowd chanted anti-Christian slogans and blocked the Australians' escape by brandishing axes before torching the car, burning to death Staines and his sons Philip, eight, and Timothy, 10.
The court heard Singh had formed a militant group of local tribals to kill Staines to stop the spread of Christianity.
The other 12 who were convicted were sentenced to life in prison but spared the gallows because the court ruled they were manipulated by Singh.
Singh, whose real name is Ravindra Pal, was arrested in Orissa's forests a year after the Staines murders.