Former White House press secretary James Brady, who was left paralyzed in the Reagan assassination attempt, looks at his wife, Sarah Brady, during a 2011 news conference on Capitol Hill. (Evan Vucci/AP)

Federal prosecutors said they will not charge John W. Hinckley Jr. with murder in the shooting of President Ronald Reagan’s press secretary in a 1981 assassination attempt, even though a medical examiner concluded that James S. Brady’s death in August was caused by the old wounds.

The decision, announced Friday by the U.S. attorney for the District, comes four months after a medical examiner decided that Brady’s death at the age of 73 was a direct result of a bullet fired 34 years ago outside the Washington Hilton on Connecticut Avenue in Northwest.

In a statement, prosecutors said their decision was based on “a review of applicable law, the history of the case, and the circumstances of Mr. Brady’s death.” Hinckley, now 59, was found not guilty by reason of insanity in the shooting of Reagan, Brady and two others and has spent the past three decades at St. Elizabeths psychiatric hospital in Southeast Washington.

Hinckley’s attorney, Barry Wm. Levine, said “any idea that this was a prosecutable case was ridiculous. There were so many legal obstacles to prosecuting this case, just countless.” He said that had authorities filed new charges, he believes the case “would be barred as a matter of law.”

The March 30, 1981, assassination attempt came just 69 days into Reagan’s presidency. Reagan was severely wounded. Brady was struck first, above the left eye, and the bullet shattered in his head. He remained incapacitated for the remainder of his life, paralyzed in the left arm and leg. At the time of his death, he was suffering from aspiration pneumonia, and prosecutors said the cause of death was listed by a medical examiner in Virginia, where Brady died Aug. 4, as a “gunshot wound [to the] head and consequences thereof.”

John Hinckley Jr. arrives at U.S. District Court on Nov. 18, 2003, in Washington. (Evan Vucci/AP)

A representative of Brady’s family said in a statement that they respect the decision by the U.S. attorney. “We deeply appreciate the extraordinary outpouring of love and support” since Brady’s death, the statement said. “We miss him greatly.”

Brady and his wife, Sarah, became leading advocates of gun control after the shooting, fighting for years for passage of legislation requiring background checks on handgun purchases.

The medical examiner’s ruling presented law enforcement authorities with a difficult decision on whether to file new charges against Hinckley, who previously had gone to trial on 13 criminal charges, two of them related to Brady: assault with intent to kill while armed and assault with a dangerous weapon. Hinckley told authorities that he hoped that killing Reagan would impress the actress Jodie Foster.

While some prosecutors said in August that the medical examiner offered authorities a new chance to revisit the criminal case, others questioned whether it would be legal or even a matter of good public policy.

U.S. Attorney Ronald C. Machen Jr., the District’s top prosector, provided two legal reasons for not pursuing additional charges against Hinckley.

In his statement, he said a judge would likely prevent prosecutors from arguing, or a jury from finding, that Hinckley was sane when he fired the shots. A jury already concluded that he was insane at the time. Machen said in the statement that any attempt to try Hinckley again would result in a directed verdict from the judge reaffirming the jury’s decision in 1982.

Machen also said the District’s now-overturned year-and-a-day law, which prevented filing murder charges 367 or more days after an attack, still affects the case because it was the law when the assassination attempt was made in 1981.

Levine also said he would have argued that the constitutional idea of double jeopardy, which protects against charging a person twice with the same crime, would have protected his client. An element of a murder charge is intent, and he said Hinckley was already adjudicated when the jury declared him insane on the “assault with intent to kill” charge. In addition, Levine said he would have argued that other medical issues caused Brady’s death.

“I think the public will understand it was a decision made professionally and with due consideration for the law and the facts,” said Joseph E. diGenova, a supervisor in the U.S. attorney’s office when Hinckley was tried. The former prosecutor said that “the criminal justice system is not perfect.” He added: “I’m sure there is nothing prosecutors would have liked better than to charge John Hinckley with murder. But they have higher duties than worrying about public sentiment.”

Although Brady’s death and the decision on how he died brought new attention to the case, Hinckley continues to battle prosecutors on another front: how much freedom he should enjoy now that it appears his illness is waning, or under control. Over the years, Hinckley’s attorney and health-care workers have petitioned to allow him stays with his mother in Williamsburg.

U.S. District Judge Paul L. Friedman ruled in December 2013 that Hinckley could visit his mother every month for 17 days. He wrote that he was convinced that Hinckley “will not be a danger to himself and to others,” but he rejected a bid for even longer outings, saying Hinckley still had not gained friends or ties to people in Williamsburg.

While in Virginia, Hinckley is under strict rules. He may drive but only to “destinations where people will be expecting him.” He is allowed six unsupervised outings away from his mother’s house, each lasting up to four hours. He is barred from visiting any areas where the president or members of Congress might be. Even the times of his daytime strolls in Williamsburg are tightly regulated. And attorneys are still debating how much Internet time Hinckley should be allowed while in Virginia.

“This is a gentleman who was ravaged by mental disease some 30 years ago and who has recovered entirely,” Levine said. “He is stricken by the grief that he has caused others. This whole event is catastrophic for him. He is keenly aware of what it did to James Brady and to others, and he regrets it profoundly.”