Janardhan Paswan, who is a Rashtriya Janata Dal (RJD) legislator from Chatra, has been accused in the murder of a government official, Mohammad Ali recently.
On its establishment day on Nov 22, every year the Jharkhand assembly confers the award to a selected member.
The assembly committee chose Paswan for the honour for the year 2010.
Reacting to the report, a BJP senior leader said, "'It is sad that a murder accused will be conferred the best legislator award. I am unable to understand how he was selected despite the fact he does not fulfil the parameters of being the best legislator."