John Hinckley Jr. shot Brady, who lived through hours of delicate surgery and further operations over the years, but never regained normal use of his limbs and was often in a wheelchair. His family said he died Monday at age 73 from a series of health issues.
Nancy Bull, district administrator for the Virginia medical examiner's office, which made the ruling, declined to disclose the results of the autopsy and referred inquiries to District police.
District police spokeswoman Gwendolyn Crump said the department was notified of the homicide ruling Friday.
Hinckley Jr. attempted to assassinate Reagan outside the Washington Hilton Hotel on March 30, 1981, just two months into the new president's term. Reagan nearly died from a chest wound. Three others, including Brady, were struck by bullets from Hinckley's handgun.
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