A man handed an indefinite jail term after attempting to rape a teenager as she made her way home at night has failed in a challenge to his sentence.

Jason Gedi (39) claimed to police his 17-year-old victim was a prostitute soliciting for business after he and another man pinned her down in an alley and attempted to force themselves on her.

Gedi, of Framland House, Pluto Close, Highfields, Leicester, was jailed indefinitely for public protection – which is almost identical to a life term – at Leicester Crown Court in December 2006, after being convicted of two counts of attempted rape.

He was ordered to serve at least four years behind bars before he could apply for parole.

Yesterday, Gedi asked Lord Justice Davis, Mr Justice Nicol and Judge Stephen Kramer QC, sitting at London's Criminal Appeal Court, to overturn the open-ended sentence, arguing it was not fair to lock him away potentially for life.

The court heard the victim of the attack was walking home along Hutchinson Walk, behind Leicester railway station, when she was set upon by Gedi and his accomplice, who pinned her down and stripped her before each attempted to have sex with her. However, "probably through drink", each was incapable of doing so.

The teenager escaped after seeking help from a passing motorist.

Lord Justice Davis refused him permission to appeal.

The ruling means Gedi, a schizophrenic, will not be freed until he can convince the Parole Board the danger he poses to society has passed.