Sajjan Kumar was acquitted in the 1984 Anti-sikh riots case by the trial court.
The CBI on Tuesday told the Delhi High Court that the police investigation into the alleged role of Congress leader Sajjan Kumar in a 1984 anti-Sikh riots case was "tainted" as it had tried to favour the politician.
The submission by the Central Bureau of Investigation (CBI) was made before a bench of justices S Muralidhar and Vinod Goel which was also told by the agency that the police kept in "hibernation" the FIRs lodged during the riots in the hope that the affected people will reconcile and settle the matter.
Senior advocate RS Cheema, the special public prosecutor for CBI, said the probe by Delhi Police was "tainted" as "FIRs were kept in hibernation, hoping that people would reconcile and settle the matter".
He made the submissions before the bench as he concluded arguments on behalf of the agency.
Retired naval officer Captain Bhagmal, former Congress councillor Balwan Khokhar, Girdhari Lal and two others were held guilty in a case relating to the murder of five members of a family in Raj Nagar area of Delhi Cantonment on November 1, 1984, during the riots that followed the assassination of the then prime minister Indira Gandhi.
Sajjan Kumar was acquitted in the case by the trial court against which both the CBI and the victims' family have appealed in the high court.
The trial court had awarded life term to Bhagmal, Khokhar and Girdhari Lal and a three-year jail term to two others - former MLA Mahender Yadav and Kishan Khokhar.
They also moved the high court challenging their conviction and the sentence awarded by the trial court in May 2013.
Senior advocate HS Phoolka, appearing for the victims, also concluded his arguments in which he has contended that Kumar has always been in a "position of influence" which he has "enjoyed with impunity" to "thwart the investigation".
In his written submissions placed before the court, Mr Phoolka has claimed that there were some charge sheets which initially named Kumar as an accused in some 1984 riots cases, but the police never filed the charge sheet and kept them in its files.
In one case where a victim/complainant had named Kumar, the police dropped his name and filed the charge sheet against the other accused, the senior advocate has said.
Mr Phoolka said that another example of Kumar's influence was seen in how the government rejected a recommendation made in 2005 by a commission, headed by retired Supreme Court judge GT Nanavati, to register an FIR against the Congress leader in connection with 1984 riots.
"Given the influence of the accused and the impunity enjoyed by him, witnesses or victims could not be reasonably expected to risk their lives and the lives of their loved ones by on their own approaching the authorities till they were assured of their safety," the lawyer said.
Arguments on behalf of Kumar would commence from October 22.