More than three decades after being found not guilty by reason of insanity in the 1981 shooting of President Ronald Reagan, John W. Hinckley Jr. appears to be nearing release from a government psychiatric hospital.

During six days of hearings before a federal judge over recent weeks, experts for U.S. prosecutors cautiously agreed with those testifying for St. Elizabeths Hospital in Southeast Washington that Hinckley, 59, is clinically ready to live with his mother in Williamsburg full time.

Instead, attorneys debated the conditions of Hinckley’s freedom if he were to be granted “convalescent leave,” because doctors say he no longer exhibits the psychosis and major depression that made him dangerous.

“If I decide to grant convalescent leave, the issues before me are the conditions of release and the financing,” U.S. District Judge Paul L. Friedman of the District said at one point as parties debated the extent and duration of a period of close monitoring, lasting perhaps two years. “I mean, we are trying to figure out how this will work in the real world,” he said at another.

Closing arguments are set for May 12, and a ruling could take weeks if not months. Hinckley’s detailed outpatient-treatment plan could be delayed or derailed if his mother dies or becomes incapacitated, if his family withdraws support or if the court is persuaded that no workable conditions can address the potential public-safety risk.

Prosecutors with the U.S. Attorney’s Office for the District have sought tighter monitoring and reporting requirements, telling the court in countless variations that no other recovering mental patient has attempted “to assassinate a president, shooting him, his press secretary and two law enforcement officers,” as Assistant U.S. Attorney Colleen M. Kennedy said.

Kennedy targeted the unknowns for which there is “no Plan B”: What happens when his mother, now 89, dies, or if he loses his family’s financial support for his treatment program, now costing $60,000 to $100,000 per year?

Hinckley’s attorney, Barry Wm. Levine, of the Dickstein Shapiro law firm, said his client should be treated like any other patient whose underlying “narcissistic personality disorder” is “highly attenuated.”

“Mr. Hinckley has a right, a right grounded in the Constitution to the least-restrictive environment consistent with public safety,” Levine said.

Hinckley was 25 when he shot and wounded Reagan, press secretary James Brady, a Secret Service agent and a D.C. police officer on March 30, 1981, outside the Washington Hilton on Connecticut Avenue NW. After Brady’s death in August, medical examiners ruled his death a homicide, the result of the wound he suffered in the attack.

Hinckley lived at St. Elizabeths full time until the 1990s, when he was permitted supervised outings with family members. Over time, amid setbacks, those trips were expanded.

In 2013, Friedman let Hinckley spend up to 17 days a month at his mother’s home, in southeast ­Virginia, under 29 restrictions meant to integrate him into the community.

At the time, the judge said he was persuaded that Hinckley “will not be a danger to himself or to others” while under strict supervision. Hinckley was told he must abide by a prearranged itinerary, log his daily activities, carry a trackable cellphone and stay away from the president and members of Congress. He is also limited to a number of unsupervised walks and short-duration trips to places where he is expected.

Now, mental-health experts testified, the next step is to gradually remove limitations, saying that flexibility will speed his recovery toward independent living. Prosecutors, however, say that more rigid limits are needed to ensure that Hinckley does not pose a threat.

Some disputes are being ironed out, such as where Hinckley might stay overnight if needed during monthly treatments in Washington; whether visits could occur outside St. Elizabeths; whether Hinckley should be limited to driving one or both of his mother’s cars, and whether one or both vehicles need location-tracking devices.

Hospital officials “adamantly opposed” a government request that Hinckley wear an ankle-monitoring device permanently, given their assessment of his low risk. Verne J. Hyde, clinical administrator of the hospital, said such a device would be “stigmatizing . . . for no reason.”

Friedman appeared to agree, especially once prosecutors conceded that the Secret Service has never activated the phone-tracking software it has long demanded for Hinckley.

The Secret Service continues to watch Hinckley — on 119 occasions in 2013 and 89 in 2014.

More complicated is prosecutors’ insistence that Hinckley be barred from setting up social media accounts — such as on Facebook — and limited to accessing the Internet through his mother’s computer, which would have tracking software to monitor his browsing history, uploads and posts.

Hyde said that employment and social opportunities for Hinckley, like the rest of society, will increasingly come from an expanding array of phones, tablets and other connected devices.

Prosecutors said unrestricted access could lead to a relapse.

“Notoriety and fame is part of [Hinckley’s] pa­thol­ogy,” explained psychiatrist Raymond F. Patterson, testifying for the government.

Releasing Hinckley is a “calculated risk,” and it “may not work,” Patterson said. “The more information you have, the better,” he said, arguing for more structure around how Hinckley spends his time, including a requirement that he continue to submit itineraries for his whereabouts.

Prosecutors noted deceptive behavior, including twice in 2011 when Hinckley told doctors that he went to a movie but instead went to a nearby bookstore and a fast-food restaurant. One of those times, a trailing Secret Service agent said that Hinckley briefly stood in front of a section of the bookstore that included several items about Reagan and the shooting.

In January, prosecutors said, Hinckley again deviated from plans, going with a photographer friend to an acquaintance’s music recording studio instead of to another photographer’s home.

While defense attorneys said that there had been a sudden change of plans after the photographer fell ill, Patterson said another doctor told him that Hinckley had called the studio the day before the trip.

“Mr. Hinckley is not forthcoming with information,” Patterson said. “That was a sense of entitlement and a disregard for the rules.”

Hinckley’s therapists called the incident a matter of bad judgment and said he had not exhibited “risk factors” of a relapse, such as depression, isolation, interest in weapons or an ego-boosting distortion of reality. Such symptoms would take weeks or months to worsen, Levine said.

Friedman asked if it was possible to monitor Hinckley while not doing so in a way that no regular person could comply.

“How do we balance the freedom, the normalcy we need to live a life, with enough mechanisms in place?” the judge asked.

If Hinckley’s condition or circumstances change or he violates a court order, he could be sent back to the hospital. Otherwise, hospital officials said that Hinckley might live independently in a few years.

Hinckley’s brother and sister estimated that in a worst-case scenario, their mother has $500,000 in savings and home equity, enough to pay for about four or five years of Hinckley’s living and medical costs at their current intensive rate, or longer if he qualified for federal or state insurance or disability benefits or his therapy needs decrease. His siblings also pledged their full support.

Scott Hinckley, 64, an energy executive, said in his business experience, the future can be unknowable “past one or two years.”

Scott Hinckley said he would not object if his brother wanted to live in Washington someday, suggesting that he might find greater acceptance in a larger city with more people familiar with mental illness. How he might do so given current orders to stay away from “government centers,” the president, members of Congress and Secret Service protectees was unclear.

Williamsburg is “very conservative,” Scott Hinckley said, and “has not been entirely welcoming — that is true.”