A New York judge decided against imposing an outside monitor on the National Rifle Association on Monday, a win for the embattled gun group and the beginning of the end of a four-year-old case brought by state regulators.

But Justice Joel M. Cohen of Manhattan Supreme Court said he wanted further assurances that the N.R.A. would overhaul its governance practices. He directed the organization and the office of Attorney General Letitia James of New York, which brought the case, to negotiate the details of a series of reform measures that he largely laid out.

The measures he proposed would change how board members are elected, purge the association’s audit committee of longstanding members and make official a number of other administrative changes that the N.R.A. had previously suggested.

Justice Cohen also barred Wayne LaPierre, the former chief executive, from serving as an officer or director of the N.R.A. for the next decade, saying he was seeking a “clear break from past practices.” A 10-year gap would give the organization time to “chart a course well distanced from the one created by this litigation,” the judge said.

The case has already upended the organization. Mr. LaPierre, who led the N.R.A. for more than three decades, retired on the eve of the trial. In February, he was found liable for misspending $5.4 million in N.R.A. funds after revelations that he had splurged on superyacht junkets, charter flights, vacations in the Bahamas and nearly $275,000 in suits from a Beverly Hills boutique.

The association’s revenue and membership have also plummeted as many members, key donors and even a few board members turned against its leadership amid the revelations about how their money was being spent. The group’s role as a political powerhouse in the Republican Party has also severely diminished, as other groups have arisen to challenge its dominance of the gun lobby.

The N.R.A. was founded as a nonprofit in New York more than 150 years ago, giving the state special authority over the group; Ms. James sued in 2020 amid headlines about lavish spending by Mr. LaPierre and other top executives.

“At this point in time, we’re relieved that we’re where we are in the process,” said Doug Hamlin, who was elected the N.R.A.’s new chief executive in May, in a brief interview outside the courtroom, after the judge announced his decision.

“We are committed to transparency and good governance and being good stewards of our membership fees, and we’re going to prove it,” he added.