The order was passed on an application moved by the CBI in the court of special judge Mirza Zeenat seeking permission to conduct a lie-detection test on the former food and civil supplies minister with his consent.
The former minister had yesterday appeared before the court and given his consent to undergo the polygraph test in connection with the murder which took place in his assembly constituency on March 2.
"I have neither changed my statement nor am I worried about anything. If CBI feels that it's necessary, then I have given my consent," he had told reporters, adding that the truth should come to the fore.
He had also said in the court that he was neither accused nor suspect in the case but if the CBI felt that his polygraphic test was necessary for the inquiry, he was ready for it.
However, CBI told the court that Raja Bhaiya was its suspect and it should be given permission to conduct this test on him.
The agency had filed its chargesheet in connection with the murder case but did not name Raja Bhaiya as accused.
Although the agency does not have any evidence which directly links Raja Bhaiya with the murder of the DSP, it wants to get a clear picture of his role, if any, in the case, CBI sources said.
They said findings of the test would not constitute evidence in the case, but it would give inputs which can be developed after thorough probe.
The agency has already grilled Raja Bhaiya on May 15 and 16 in the murder case.
Haq was shot dead in Balipur village in Kunda area of Pratapgarh district where he had gone to probe the murder of village head Nanhe Yadav.
The deceased police officer's wife Parveen Azad had accused Raja Bhaiya of hatching a conspiracy after which he had to resign from the Cabinet on March 4.
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