Yale Law School Dean Harold Koh, who has emerged as one of the most visible leaders of the opposition movement to the domestic eavesdropping program of President George W. Bush ’68, will call for an immediate end to judicially unauthorized spying before a full session of the Senate Judiciary Committee this morning.

Koh will address the body at around 10 a.m., second out of seven witnesses scheduled to testify tomorrow, in a hearing titled “Wartime Executive Power and The National Security Agency’s Surveillance Authority.” His prepared testimony acknowledges the increased need for intelligence in an age of global terrorism, but criticizes the Bush administration for what he describes as its “blatant” violation of the Fourth Amendment, federal statute and judicial precedent, and also for threatening the federal government’s separation of powers.

“It’s almost breathtaking that a decision was made to step outside the legal framework, do so secretly, do so on a large scale, and then when it comes to light, to argue that the extra-legal framework is actually lawful,” Koh said Monday, hours before departing on a train with his son to Washington, D.C. “Over time, I’ve learned that you just have to make the argument that you believe is legally correct and hope that people are moved. I’ve won some and I’ve lost some.”

Koh, who has testified more than a dozen times before Congress — most recently to oppose the confirmation of Alberto Gonzales to his current position of attorney general — will sit on the panel alongside legal scholars and former government officials. On the opposite side of the spectrum, Pepperdine Law School professor Douglas Kmiec, who is also scheduled to testify today, said he disagrees with Koh’s assessment of judicial precedent.

“Congress has the authority to provide resources for the military and provide rules and regulations for the Army, but it has long been conceded as part of history and practice that the president is the tactician,” Kmiec said. “I think [Koh] is a person of good faith, but I think he makes his argument largely based on statutory provision. … It’s a statutory argument that has to be in the context of the entire statute and the Constitution.”

But constitutional law scholars said the distinguishing factor in this polarizing debate is that claims of illegality have transcended political partisanship. Bruce Fein, who will be testifying in strong opposition to the program, was also a prominent conservative who served under two Republican administrations.

“I consider this the most threatening danger to our civil liberties since Watergate,” Fein said. “I view my opposition as opposition based on the most conservative principle: that men aren’t angels … which underwrites virtually all of our constitution. ‘You can leave me as a platonic guardian of all your liberties’ is Rousseauan, utopian and reminiscent of 1960s government, [which said,] ‘You can just let us do anything.'”

Fein will propose to Congress that it should prevent the president from continuing the program by employing the power of the purse to prevent any money from being spent on domestic spying. He said he welcomes Koh’s testimony, although the two have frequently clashed, because he does not view the issue as partisan but rather as one rooted in the principles of American democracy.

“One of the major [criticisms] of Bush is he thinks that if you don’t kowtow and play an obsequious role, you’re an enemy,” he said. “The idea of constructive criticism is beyond this guy’s mental universe.”

Ken Gormley, a Harvard classmate of Koh’s who will testify against the program, said he is optimistic that Congress will act in line with the suggestions to be made by Koh — who co-wrote an open letter to Congress opposing the program last month — by adopting measures that involve the courts in obtaining warrants and call more explicitly for Congressional oversight.

“All indications are that the senators are working very hard and are very seriously trying to do the right thing here,” Gormley said.

Although there was little buzz over the impending testimony of Koh at the Law School on Monday afternoon, some law students said the issue is hotly discussed in classrooms but not polarizing, since most students support Koh.

Dakota Rudesill LAW ’06, who researched for Koh in preparation for his testimony and followed him to the Capitol today, said he thinks as “one of the nation’s foremost experts on national security law,” Koh will provide a thorough understanding of the pertinent legal issues.

“The thing that I find so remarkable about him is that he gets to the law and policy on all levels,” Rudesill said. “Highly detailed levels, like I received in his civil procedures class, all the way up to the big picture of saying what is the way national security divisions are supposed to be made. It’s kind of a full spectrum of confidence.”

Daniel Freeman LAW ’07, who is also engaged with Koh’s national security work, said the Law School — which will be flooded this morning with a new issue of the student magazine “Opening Arguments” that focuses mainly on the intra-school debate over NSA spying — said he thinks Koh aptly represents the views of the Yale student body.

“A very, very large percentage of the Law School is going to agree with Dean Koh on this one,” he said.

But Koh said he urges those in the community who disagree to make their voices heard, especially if they defend their position forcefully and on behalf of public interest.

“We’re not just another professional school, and we don’t think our students should be just another group of lawyers,” he said. “They should be speaking out for affirmation of public values through the law. I see [testifying] very much as part of my job as dean.”