England's World Cup campaign so far has been shrouded in controversy, with centre Mike Tindall grabbing a number headlines after being caught on CCTV hugging and kissing a woman just weeks after his marriage to the Queen's granddaughter Zara Phillips.
"[Their behaviour] is beyond belief," said former outside centre Guscott. "To tell you the truth it is staggering.
"Martin Johnson's got a few kids on the squad that aren't acting as though they're playing for England, or at a World Cup.
"The last thing Johnson wants is to be sat at a press conference having to fire fight questions from journalists."
England have reached the quarter-finals of the competition and face France this weekend for a place in the final four.