The Delhi Police had sought the custody of Singh, brought in court on Thursday on a production warrant, for interrogation and a potency test to be carried out on him in the case of rape of a 42-year-old woman.
As police contended that the MP has to undergo potency test as it is mandatory process to prove the rape allegation, Metropolitan Magistrate Babita Puniya allowed them to quiz him.
Police also told the court that the MP was not cooperating with them in the investigation. Dhananjay Singh's advocate SPM Tripathi, however, told the court that his client is cooperating in the probe and he has nothing more to tell the investigators.
The MP was booked under Sections 376 (rape) and 506 (criminal intimidation) of the Indian Penal Code after the woman filed a complaint at East Delhi's Pandav Nagar police station, claiming that the MP raped her several times at gunpoint.
"The woman, a government employee, alleged that she was sexually assaulted by Dhananjay Singh at her house in east Delhi's Mayur Vihar Phase-I several times between July 2005 and March 2009," an officer said.
The BSP leader is currently in judicial custody on charges of destroying evidence to shield his wife, Jagriti, who was arrested for torturing her maid, leading to her death.