Kumud Kumar, Sanjay Biswas and Santosh Kumar were sent to jail after their bail petition was rejected by the Chief Judicial Magistrate in Bhagalpur, about 200 km from here.
Mohd Rustam, in his mid-20s, had filed a complaint against the trio for allegedly torturing him like an animal in custody after he refused to become a witness in a murder case.
"The CJM court has sent the three police officers to 14 days judicial custody," police said.
He also alleged that the three had extorted money from him, and later made him an accused in the same murder case.
In 2013, the court took cognisance of the case against the three policemen after which it issued a non-bailable warrant against them on February 14, 2014.