Speaking today at the Lord Leveson inquiry into press ethics and standards, Lewis said that preserving the current system of self-regulation of the press was "the preservation of no regulation at all".
Lewis represented Professional Footballers' Association chief executive Gordon Taylor in his phone hacking case against News Group News, a subsidiary of News International, which was eventually settled with a payout of £425,000 plus his legal costs.
He also secured injunctions on behalf of former footballer Garry Flitcroft, who gave evidence to the inquiry yesterday, and Jo Armstrong, a legal advisor at the PFA.
Armstrong's injunction was secured after the News of the World secured a photo of her and Taylor for a story, which Lewis was able to block before publication.
He told the inquiry that he had a "eureka moment" after realising that the only way News International's now-defunct Sunday tabloid could have got the story, which was untrue, was not through "proper legitimate investigation", but through phone hacking.
He claimed that a tabloid journalist had listened to Armstrong's voicemail message to Taylor thanking him for speaking at her father's funeral, and "added two and two and made 84".
He added: "If it hadn't been so sad it would have been funny."
Lewis, who was allegedly the victim of surveillance by the News of the World, said that most attention in the phone hacking scandal had been on the paper, but he claimed to have evidence from his clients that other organisations were involved.
"It was a much more widespread practice than just one newspaper," Lewis said.
He said that voicemail interception was such an easy-to-access practice that many journalists would use it just to "pry on things".
"I don't think they necessarily thought of it as any worse - certainly at the beginning - than driving at 35mph in a 30mph zone," he added.
> News of the World hacking more widespread, says lawyer
Lewis said that he was portrayed as "greedy" and sanctimonious" as he represented more alleged victims of phone hacking, admitting that he "became part of the story".
The lawyer represents the family of murdered schoolgirl Milly Dowler, who on Monday told the inquiry that the hacking of their daughter's phone in 2002 tragically made them think she was still alive.
Lewis further claimed that he had been warned Daily Mail editor-in-chief Paul Dacre would sue him if he made any suggestion that the paper was involved in the scandal.
This week has seen a war of words erupt between Hugh Grant and the Daily Mail, after the actor alleged that the paper had hacked his phone for a story on his relationship with Jemima Khan.
The Daily Mail issued an immediate and strong denial of the charges, and also accused Grant, a committed campaigner against press intrusion, of a "mendacious smear" against the paper.
Yesterday at the inquiry, Steve Coogan accused the media of acting "like the Mafia" after journalists had allegedly rooted through his bins and tried to trick him into revealing details of his personal life, just to get a story.
Also today, Lord Leveson will hear evidence from Sheryl Gascoigne, the former wife of ex-footballer Paul, the parents of missing girl Madeleine McCann and journalist Tom Rowland.