A senior police official said they "spoke with" Bhushan during the day to ascertain some facts regarding the CD, which the lawyer had claimed, was doctored.
The questioning came days after Team Anna upped its ante against government levelling allegations against Prime Minister Manmohan Singh and 14 other Union Ministers.
However, police denied any suggestions that their action was related to Team Anna's action.
A close associate of Bhushan said the lawyer was intimated about the questioning. "Police had informed him earlier. They had taken permission," he said.
The CD contained purported conversation between Bhushan and the leaders where the lawyer allegedly promised that a judge could be influenced for a price and his son and lawyer Prashant Bhushan would facilitate this.
