In its report filed before the high court, the CBI said Patil and two others -- Ulhas Patil and Ramesh Choudhary (Congress leaders from Jalgaon) -- refused to undergo lie detector test.
The agency, however, gave a clean chit to Patil saying that there was no evidence of his involvement in the conspiracy to murder Vishram Patil, former president of the Jalgaon district Congress.
He was murdered on September 21, 2005, and his wife Rajni had moved the high court last year, saying that the CBI has not probed Patil's alleged role.
Giving reasons as to why Patil was not involved in the murder, the CBI said it found as inadmissible the claims made by Raju Sonawane, an accused chargesheeted by the agency, implicating Patil and two others for allegedly conspiring with Raju Mali, another accused, to eliminate Vishram Patil.
Eyewitness Rambhau Gobru Pawar had named G N Patil, Ulhas Patil and Ramesh Choudhary but the CBI claimed the same could not be corroborated.
Sonawane, a chargesheeted accused, had pointed to a house where the conspiracy had taken place. The building was Dr Ulhas Patil's hospital, but the staff there denied that he had ever visited the place.
'The evidence mentioned do not inspire confidence and credibility. Therefore, there is no evidence of the involvement of G N Patil in the conspiracy.
'Similarly, there is no evidence of the involvement of Ulhas Patil, Ramesh Choudhury and anybody else in the conspiracy though there may be inter-se political difference or dispute...' the CBI said in its report.
The Bombay high court last week deferred hearing in the murder case till December 3.
The CBI had filed a chargesheet on October 6, 2008, against Raju Mali, Raju Sonawane, Leeladhar Narkhede and Dasmodar Lokhande and had stated that they had not found any evidence linking G N Patil to the case.
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