John Hinckley, who attempted to assassinate then-President Ronald Reagan in 1981, is slated to be freed on unconditional release next year.

Hinckley shot Reagan in Washington, DC, along with three others, in a failed attempt on the former president's life. Hinckley's lawyer said the "momentous event" of full release next June is both appropriate and required by the law.

Hinckley, now 66, has been living outside a mental health facility for the past several years, a gradual lightening of supervision. His doctors have given Hinckley an "excellent" prognosis, NPR reported.

"Very few patients at St. Elizabeths Hospital have been studied more thoroughly than John Hinckley," commented US District Judge Paul Friedman.

Hinckley was previously found not guilty of his crimes due to insanity, at which time he was committed to St. Elizabeth's Hospital in Washington, DC.

He was allowed to move in with his mother in Williamsburg, Virginia, nearby. His mother recently died at age 95 in her sleep this summer, and since then, Hinckley has continued to live alone at the same address.