Hinckley is wrestled to the ground after firing shots at the president and his entourage

At a hearing to be held in Washington on 2 September, John Hinckley, 48, will argue that he poses no danger to society and ask to be allowed unsupervised leave from the Washington institution where he has been held for more than 20 years.

Mr Hinckley will ask for unsupervised visits to his parents' home. If approved, this could be a step towards eventual full release.

Mr Hinckley fired six shots outside the Washington Hilton in March 1981 after approaching the presidential entourage. He wounded President Reagan, his press secretary James Brady, and Thomas Delahunty, a police officer.

In new court documents, Mr Hinckley's lawyer, Barry Levine stated: "It is undisputed that Mr Hinckley's psychosis and depression have been in full remission and that he has shown no symptoms thereof for over a decade.

"Mr Hinckley does not pose a risk of danger to himself or others now or in the reasonable future."

Reagan's daughter

But Mr Reagan's daughter Patti Davis is fighting Mr Hinckley's release from St Elizabeth's Hospital.

"The man plotted carefully to go down in history as the man who killed President Reagan," she said.

Hinckley appeared in court in neat three-piece suits

In an article for Newsweek, she said that she did not believe that Mr Hinckley is "no longer mentally ill".

"I don't believe mental illness means a person is not extremely smart, deceptive and calculating," she added.

Mr Hinckley was a celebrity stalker, but his case was unusual. He was motivated by an obsession with actress Jodie Foster to try to kill President Reagan.

He believed he could win Miss Foster's affection by emulating the central character in the cult movie, Taxi Driver, in which she starred alongside Robert De Niro.

Like Robert De Niro's character Travis Bickle, Mr Hinckley bought guns. He also stalked Miss Foster. But Mr Hinckley could not have been further from the De Niro character.

Fantasies

The image that endures from his criminal trial is that of a pink-cheeked, cherubic-faced man in his mid-20s with neat three-piece suits. This contrasted with Travis Bickle's leather jackets and Mohican-style hair.

Hinckley was obsessed with actress Jodie Foster

Mr Hinckley's defence sought to project him as a teenage failure, with problems tracing back to adolescence. They painted a picture of someone who was withdrawn, who had no friends and began inventing make-believe characters. Eventually, they said, he believed his own fantasies.

The prosecution rejected the image of a tormented man driven by an obsession with Miss Foster.

But he was found not guilty of attempted murder by reason of insanity.

The public was so outraged that some US states began drafting legislation to abolish use of the insanity defence. It was only outlawed in a handful of states, but, in others, the definition was substantially narrowed.

Mr Hinckley has been allowed supervised trips out of St Elizabeth's for some time. He has been to shopping malls, bowling alleys, bookshops and cinemas. At times, he has been accompanied by friend Leslie de Veau, a former patient at the institution who was found not guilty by reason of insanity of the murder of her 10-year-old daughter.

Mr Hinckley's efforts to win additional freedoms have often been frustrated by disclosures.

In late 1987, applications for his release were withdrawn when he was discovered with a stack of photographs of Miss Foster hidden under his mattress. He was also found to have corresponded with convicted serial killer Ted Bundy.