Kohei Nakabo, arguably one of Japan's best-known lawyers, gave up his practice Friday after being questioned by prosecutors over allegations that he swindled a creditor while heading a quasi-governmental debt-collection body.

The 74-year-old is a former chairman of the Japan Federation of Bar Associations and also served as president of Resolution and Collection Corp. He submitted documents to the Osaka Bar Association on Friday morning that nullify his registration as a lawyer and a member of the local lawyer body.

During a subsequent news conference, Nakabo said he was aware of the swindle.

"When I first heard of the plan, I thought it was a rather selfish deal, but I was convinced after listening to the explanation of those involved," Nakabo said.