No sooner than that scandal had died down, it was revealed that Johnson had to reprimand three of his squad - James Haskell, Chris Ashton and Dylan Hartley - for their treatment of a female hotel worker in Dunedin.
Guscott, who won 65 England caps said: "The last thing Johnson wants is to be sat at a press conference having to fire-fight questions from journalists."
The players had to understand that they were representing their country and the stories of "messing about and drinking" were completely unacceptable.
"This is a Rugby World Cup. If you think you're living in a goldfish bowl wait until the 2015 Rugby World Cup [in England]. They'll be under a microscope then," he said.
Guscott was in the same England team as Johnson for the 1999 World Cup and a member of the England squad that lost to Australia in the 1991 World Cup.
Former England captain and manager Roger Uttley said there had been "embarrassing indiscipline on and off the field for Martin Johnson".
"I'm sure he's got a grip of these guys and laid down what responsibilities they have as individuals, and as a team who are representing England," he told the BBC.
"As a former England player I'm embarrassed that we're seen in this light - an archetypal stereotype of a rugby player that used to be the case but no longer should be."
But England wing Mark Cueto believed the incidents involving his teammates had been blown out of proportion.
"If the boys can't go out and have a few beers then it is a sad world that we live in," he told the BBC.