Darryn Lyons: 'Being a celebrity is a choice'
Darryn Lyons, who runs Big Pictures, said the rules governing the industry were "extremely ambiguous" and photographers did not know what was "right or wrong" because celebrities frequently changed their mind about being photographed.
Giving evidence to the Leveson inquiry by video link from Australia, Lyons said: "Celebrities court publicity when they want to court publicity, and then all of a sudden they want to switch it off.
"On one day we're doing a setup with Naomi Campbell through her or her management and all of a sudden she's sending through some kind of legal action for privacy.
"The problem with the industry as we face it today is that photographers and picture agencies and publishers really don't know where they stand. It's extremely ambiguous."
He said many celebrities profited financially from having their photographs taken "on their terms" - and PRs frequently tipped off photographers about their clients' movements to ensure maximum publicity.
"Being a celebrity is a choice of the person," Lyons said. "The fact of the matter is that if you are in the public eye you are looked up to. We live in a world of voyeurism. It is a business.
"You don't know when you're photographing celebrities these days whether it's right or wrong."
Lyons was asked about a string of injunctions and complaints made against Big Pictures by celebrities including JK Rowling and Sienna Miller.
He said there was "no doubt that photographers have been disciplined" in the past for misconduct - but he could not remember the exact circumstances - and said he was not responsible for the actions of freelance photographers who were not directly employed by the agency.
Lyons also claimed that photographers were passing themselves off as Big Pictures representatives and tarnishing the company's reputation.
"It is a huge problem," he said. "It has happened on many occasions and caused us no end of grief - people from competitive agencies or freelance photographers giving false names and saying they're from Big Pictures."