The glitch in the law could prove to be very dangerous, as it allows rapists and paedophiles, like rocker Gary Glitter, 64, to move about freely and to go about their activities undetected.
Those convicted of crimes, but later released, need to sign the Sex Offenders' Register, which is designed to keep track of perverts.
Judge Anthony Scott-Gall has branded the loophole "astonishing", after he heard of it when a homeless sex offender appeared at Lewes Crown Court, Sussex, after going missing for nearly three years.
"How do the police keep track of people who have no fixed address?" Daily Star quoted the judge as asking.
Prosecutor Barbara Down further explained to him how the loophole worked.
"Apparently, it is perfectly acceptable to sign the register with a particular bus stop or public bench as your home address," she said.
"Offenders can even put down 'The third tree on the left in Friston Forest' if they want," she added.
Shaking his head, the judge said: "That's quite astonishing."
After the hearing, Yvonne Traynor, of the Rape and Sexual Abuse Support Centre UK, was quite furious that such a thing could be allowed to happen.
"This makes a mockery of the system," she stated.
"If the police are not keeping tabs on these people, we're all in big trouble," she added.
Mappa, which runs the Sex Offenders' Register, confirmed the bizarre addresses can be used, the only thing offenders need to do is to inform the police if they are moving.