WASHINGTON (CNN) — A hearing continues Thursday to determine the future of John Hinckley Jr., who shot President Ronald Reagan and three others in March 1981.

After an expected week and half of testimony, a federal judge will consider whether Hinckley should eventually be released from a mental hospital, where he has been a patient since his 1982 trial. The trial ended in a jury verdict of not guilty by reason of insanity.

On Wednesday, Hinckley’s lawyers said he is not dangerous and should eventually be released. But prosecutors are fighting that, saying Hinckley has been deceptive about his activities while on visits to his mother in Williamsburg, Virginia.

In opening statements, prosecutor Sarah Chasson said Secret Service agents will testify they performed surveillance on Hinckley without his knowledge earlier this year when he was allowed what he was told was unsupervised free time in Williamsburg.

On several occasions in July and September, Hinckley was supposed to go to the movies or shopping but instead went to bookstores where he looked at books about Ronald Reagan and presidential assassins, Chasson said. A requirement of Hinckley’s current visitation program is that plans be laid out detailing what he will do when on his own and that medical staff and the Secret Service are informed.

According to Chasson, in the first instance in July, Hinckley was supposed to go to the movie “Captain America.” Later when he saw his “treatment team,” Hinckley not only maintained he had gone to the movie, but he enthusiastically recommended it.

Chasson also quoted from a 1987 diary entry by Hinckley in which he said “psychiatry is a guessing game” and doctors “will never know the true John Hinckley.”

“The hospital doesn’t know what Mr. Hinckley is thinking, and he wants it that way,” the prosecutor said.

Hinckley’s attorney, Barry Levine, said the issue is not whether Hinckley has sometimes been deceptive but whether he is dangerous.

“This man is not dangerous and the evidence shows he is not dangerous,” Levine said. He added that Hinckley is “flawed” but is “fundamentally decent.”

Levine said that in the two and a half decades that Hinckley has been at St. Elizabeths Hospital in Washington to undergo treatment and during his visits outside that facility, there has “not been a single act of violence.”

Since 1999, Levine said, Hinckley has been taking a drug called Risperdal. Medical websites describe Risperdal as an antipsychotic medication often used to treat bipolar disorder and schizophrenia.

Dr. Tyler Jones, director of psychiatry at St. Elizabeths, testified Hinckley also started taking Zoloft in 2005 after complaining about anxiety.

Jones said Hinckley had been diagnosed years ago as suffering from depression and from an unspecified psychotic disorder. But Jones said he’s been in remission for both of those disorders for many years. He said Hinckley also suffers from narcissism, which has improved but is still present. Jones said he has interviewed Hinckley but has not treated him.

According to Jones, Hinckley’s treatment team was informed by the Secret Service that Hinckley had not told the truth about his activities during several visits. Jones said the medical staff discussed this issue with Hinckley, who initially did not appear to view the issue as a big deal, but later understood it was a serious issue.

Although concerned Hinckley was not truthful about his activities, Jones said, “We didn’t feel this constituted an increased risk.” The staff decided to reduce Hinckley’s Christmas visit to his mother from 10 days to five days, and he will not be allowed to have any unaccompanied activities during that December stay. Jones said the staff had considered stronger action including the possibility of revoking Hinckley’s privileges altogether.

A September filing by prosecutors said Hinckley “continues to be deceptive regarding his relationships with and interest in women.” According to the document, in June of 2009 he went on the Internet to find photos of his female dentist. “When he was caught, Hinckley claimed, falsely, that the dentist had invited him to view her personal photographs.”

Asked about the photographs of the dentist, Jones said the photographs were of the woman graduating from dental school and were “not salacious.”

He said the hospital considers Hinckley “a low risk of violence to himself and others.”

Currently, Hinckley is allowed to visit his mother 10 days a month. On July 29, St. Elizabeths Hospital filed a proposal to increase that. The first step would allow Hinckley to have two visits of 17 days. That would be followed by six visits of 24 days.

According to the September government filing opposing the plan, the hospital would then “be given the sole discretion to place Hinckley on convalescent leave in his mother’s hometown.”

After the judge and all the lawyers were in place, Hinckley, now 56, entered the court wearing a brown sports jacket, dark pants and a striped tie. He shook hands with all his lawyers and sat down. U.S. District Judge Paul Friedman greeted Hinckley and he replied, saying, “Good morning.”

Hinckley’s defense team has listed him as a possible witness at the proceedings but has not revealed if he will definitely testify. Prosecutors want to cross-examine Hinckley and his defense lawyers oppose that.

Mental health experts and Secret Service agents will testify, along with Hinckley’s brother and sister. Hinckley’s mother is now 85 years old and is not a scheduled witness.

It’s not clear how quickly the judge might issue a ruling on the hospital’s plan to gradually allow Hinckley greater freedom.

On March 30, 1981, Hinckley waited for President Reagan to leave a Washington Hotel after a speech. He opened fire and hit Reagan, his press secretary James Brady, Secret Service agent Timothy McCarthy and Washington police officer Thomas Delahanty. All survived, but Brady suffered a serious head wound that permanently affected his mobility and his speech.

Hinckley, who was 25 at the time of the shooting, was enamored of actress Jodie Foster. He left a letter addressed to her in his Washington hotel room saying, “Dear Jodie. There is a definite possibility I will be killed in my attempt to get Reagan.”

— By Carol Cratty