Coming down heavily on the lawmaker, the new JD(U) president said the issue is related to ethics and "if the Rajya Sabha takes any decision to dismiss him on this ground, the party will welcome the logical step."
About Mr Sahni continuously pleading innocence and refusing to quit from the Upper House, Mr Kumar castigated him by commenting, "You alone is speaking truth!"
"CBI chargesheeted Sahni and Rajya Sabha Chairman Hamid Ansari gave approval to CBI to prosecute him. The Chairman must have given his permission only after perusing all necessary documents," he said and refused to defend the lawmaker.
"Even after this if you (Sahni) have to fight the charge, go to court and do it legally after quitting Parliament," Mr Kumar said adding "this (display of morality by resigning) would have created good impression about him within the party instead of embarrassing it which he did by his conduct."
"You have not been elected by the people, but the party sent you to Rajya Sabha twice. You should have displayed morality and quit after the Chairman gave nod for the prosecution," he said.
Anil Sahni was sent to Upper House after the demise of his lawmaker father Mahendra Sahni in January 2010.
Stating that the party has served the lawmaker showcause notice and he has to it reply within a week, the JD(U) chief said, "We will not hesitate to take stern action against him after the time to reply to the showcause notice ends."
CBI had filed a chargesheet against Mr Sahni alleging that he conspired with other persons and used forged e-tickets and fake boarding passes to defraud Rajya Sabha to the tune of Rs 23.71 lakh as travel and dearness allowance reimbursement without undertaking the actual journey.
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