Police failed to tell Liberal Democrat deputy leader Simon Hughes that Glenn Mulcaire had his address, home phone number, the Leveson Inquiry heard.
Scotland Yard detectives informed Mr Hughes in October 2006 that they had uncovered evidence the private investigator had hacked his mobile phone.
But it was May last year before police shared with Mr Hughes the extent of the information that Mulcaire held about him.
Mr Hughes strongly criticised Scotland Yard's failure to bring charges against anyone else despite evidence that "at least three" other senior News of the World journalists were involved in hacking his phone.
Referring to his original contact with police in 2006, he said: "What they didn't tell me was that Mr Mulcaire not only had that phone number but he had every other phone number, address, and other things.
"They did not tell me that he had, for example, the hotline in the office, which only a few people knew, my private phone number at home, which is private because four years before or something like it I had been a witness in a murder case and had had to have police protection."
He said the investigator's notebooks showed that the News of the World had tried to stand up stories about a man and a woman linked to him "based on a salacious assumption".
"They were trying to establish relationships between me and these people, neither of which were what they would have liked them to have been," he said.
More top news
Speaking publicly about their divorce for the first time, the actress said she is confident she and Brad Pitt will remain a family unit.
Misty low cloud and some patchy fog again tonight but with mild air
Former world title challenger Michael Watson and his carer were assaulted by would-be thieves in an apparent car-jacking attempt.