Former National Security Agency employee Thomas Drake accepted a plea deal Thursday that cleared him of espionage charges stemming from an alleged leak of classified information to a Baltimore Sun reporter who wrote about waste and mismanagement at the intelligence-gathering operation at Fort Meade.

Defense lawyers said Thomas Drake leaked information to expose waste at the National Security Agency. Drake, who was scheduled for trial in federal court in Baltimore on Monday, instead is to plead guilty today to a misdemeanor charge that he exceeded the authorized use of a computer. The government dropped 10 more serious felony charges that could have sent him to prison for as long as 35 years, and he is now expected to serve no prison time.

"He feels a profound mixture of emotions after five years of investigation and one year of being under indictment," said Jesselyn Radack, a supporter and a director at the Government Accountability Project, which advocates and seeks to protect whistleblowers. Drake is not allowed to comment until after this morning's appearance before U.S. District Judge Richard D. Bennett, she said.

The one-time senior NSA manager was indicted last year on charges of taking classified information for the purposes of leaking it to then-Sun reporter Siobhan Gorman, who wrote a series of articles detailing problems with some of the agency's counterterrorism programs. Gorman, who was not named in the indictment, now works at The Wall Street Journal.

Spokeswomen for The Sun and The Journal declined comment on the plea deal.

The Drake case is one of five that the Obama administration has been pursuing against those accused of leaking government secrets — a trend that alarmed advocates of greater transparency in government.

Gorman wrote articles for The Sun in 2006 and 2007 about flawed programs at the NSA, including an expensive antiterrorism technology called Trailblazer that was embraced by the agency but later abandoned.

The "feeble" result of the Drake prosecution does not bode well for the other cases, although in some of those the government has stronger arguments at its disposal, said University of Maryland law professor Michael Greenberger. He was critical of the government for applying the "overly broad and vague" Espionage Act, which is generally used against spies like Aldrich Ames, to someone who had exposed problems with NSA programs.

"I think to the extent that the government wants to teach those working in the intelligence infrastructure by using an elephant gun, they've lost a lot of footing," said Greenberger, a former top counterintelligence official with the U.S. attorney's office during the Clinton administration. "This was a very tough case in that it did not evoke the kind of outrage from the public that someone had placed the country in harm."

There had been some signals in the past week that the government's case against Drake might be faltering.

In a letter dated Sunday, prosecutors told Bennett that they would withdraw four exhibits and redact two others that refer to "a particular telecommunications technology."

Prosecutors apparently sought to reword classified documents that were deemed too sensitive to be introduced as evidence. But, as the letter notes, the judge ruled June 3 that those substitutions "would not provide the defendant substantially the same ability to make his defense."

Additionally, supporters of Drake said that prosecutors had previously offered two other plea deals, indicating a desire not to take the case to trial.

"I think it's an acknowledgment on the government's part that they had exceedingly tough sledding ahead," Greenberger said.

"The judge's order that limited their documents obviously hurt them."

The law professor said another case the administration is pursuing, against Bradley Manning, the former Army intelligence analyst accused of providing information to the WikiLeaks website, would be a better test of the boundaries of whistle-blowing.

"The WikiLeaks case is going to be more evident of whether there are deterrents in the law to reckless disclosure of information," he said. "This case did not rise to that level."

"This whole thing was to shut people up," said former NSA mathematician Bill Binney, a Drake ally whose home was raided in July 2007 by federal agents as part of a leak investigation. Binney, who was not charged, claims that the probe was in retaliation for a complaint to the NSA's Inspector General about what he viewed as mismanagement related to contracts for a massive surveillance program.

Others, though, rued the result of the Drake case.

"I think it's sad. It sends all the wrong signals," said Robert Turner, co-founder of the Center for Law and National Security Law at the University of Virginia School of Law.

"I think what he did was a betrayal of trust, and he's essentially walking on it."

Turner said that allowing government employees to leak secrets without facing strong penalties has serious consequences for national security. "If we cannot keep secrets, we will not get many secrets," said Turner, a former intelligence adviser in both the White House and Congress.

Turner said he wasn't faulting the prosecutors, and in fact, praised the Obama administration for going after Drake and others accused of leaking government secrets. The fact that prosecutors had to withdraw and redact documents indicates the level of sensitivity of information that the government must protect, even at the expense of letting Drake off on a much-reduced charge.

"The reality of it is some of the best evidence, they could not reveal," Turner said.

Under the plea agreement signed by both sides on Thursday, Drake admits to exceeding his authorized access and obtaining information from the government. While the maximum sentence for this offense is one year in prison, the U.S. attorney's office agreed not to oppose a "noncustodial sentence" and to dismiss the other counts against Drake.

Drake had rejected the previous settlement offers because he was "adamant that he would not plea bargain with the truth," Radack said.

She said the case could have established "a horrible precedent" had Drake had been found guilty of espionage charges. Whistleblowers who reveal government wrongdoing, she said, are not spies.

"If you paint someone with the word espionage," Radack said, "you paint them with the brush of being a traitor to their country."

Los Angeles Times reporter Ken Dilanian contributed to this article.