John Hinckley Jr, who shot and wounded US president Ronald Reagan in 1981, has been freed from court oversight, officially concluding decades of supervision by legal and mental health professionals.
"After 41 years 2 months and 15 days, FREEDOM AT LAST!!!," he wrote on Twitter shortly after 12pm on Wednesday.
The lifting of all restrictions had been expected since late September.
US District Court Judge Paul L Friedman in Washington DC said he would free Mr Hinckley on 15 June if he continued to remain mentally stable in the community in Virginia where he has lived since 2016.
Mr Hinckley, who was acquitted by reason of insanity, spent the decades before that in a Washington DC mental hospital.
Mr Hinckley's restrictions were gradually loosened over the years, including the lifting of limits on his social media use. Mr Hinckley's following on social media has grown to nearly 30,000 followers on Twitter and YouTube over the past several months.
Freedom for Mr Hinckley will include giving a concert - he plays guitar and sings - in Brooklyn, New York, that is scheduled for July.
But the greying 67-year-old is far from being the household name that he became after shooting and wounding the 40th US president — and several others — outside a Washington DC hotel.
Today, historians say Mr Hinckley is at best a question on a quiz show and someone who unintentionally helped build the Reagan legend and inspire a push for stricter gun control.
"If Hinckley had succeeded in killing Reagan, then he would have been a pivotal historical figure," HW Brands, a historian and Mr Reagan's biographer, wrote in an email to The Associated Press.
"As it is, he is a misguided soul whom history has already forgotten." Barbara A Perry, a professor and director of presidential studies at the University of Virginia's Miller Center, said that Hinckley "would be maybe a Jeopardy question".
But his impact remains tangible in Mr Reagan's legacy. "For the president himself to have been so seriously wounded, and to come back from that - that actually made Ronald Reagan the legend that he became ... like the movie hero that he was," Ms Perry said.
Mr Friedman, the federal judge overseeing Hinckley's case, said on 1 June that Mr Hinckley has shown no signs of active mental illness since the mid-1980s and has exhibited no violent behaviour or interest in weapons.
"I am confident that Mr Hinckley will do well in the years remaining to him," the judge said during the hearing earlier this month.
He noted that lawyers for the government and Mr Hinckley have fought for years over whether Mr Hinckley should be given increasing amounts of freedom.
"It took us a long time to get here," he said, adding there is now unanimous agreement: "This is the time to let John Hinckley move on with his life, so we will."
