In 2002, John Kiriakou, an officer with the Central Intelligence Agency, looked into the face of terrorist Abu Zubaida, the third-ranking official in al-Qaida, after he was captured in Pakistan.

Yesterday, Mr. Kiriakou looked into the faces of University of Pittsburgh students to discuss whether the CIA's interrogation techniques used on Mr. Zubaida -- including the controversial practice of waterboarding -- were effective and morally defensible.

Effective? Undoubtedly, said Mr. Kiriakou, 43, a native of Sharon, Mercer County, who retired from the CIA in 2004 after 14 years with the agency. The information obtained from Mr. Zubaida disrupted dozens of planned terrorist attacks, he said.

The other question, however, is tougher, as Mr. Kiriakou acknowledged during his lecture, "Ethics in Intelligence," delivered to a group of more than 150 students and others gathered in David Lawrence Hall in Oakland.

"The whole agency, after Sept. 11, everybody in the building volunteered to go to Afghanistan," said Mr. Kiriakou, who never used any of the "enhanced techniques" himself. "We wanted to do something to bring these guys to justice. And we needed to act quickly" because officials thought another strike was pending.

Waterboarding was approved and used because of that sense of urgency, he said.

"In that very specific case, I think the ends justified the means," he said. "[But] we've had 6¹/₂ years to develop sources inside al-Qaida and to improve our relations with other countries and their intelligence services to the point that we shouldn't need to do waterboarding now. We should be all over these guys by now. And I think [it's working] because we haven't had another attack on U.S. soil."

A self-described "lifelong liberal Democrat" raised in New Castle, where his mother still lives, Mr. Kiriakou was content with his post-CIA career running an international business risk analysis firm. But then he saw the controversy over waterboarding erupt, and he said he couldn't stay quiet.

"Accusations were being leveled against the agency by members of Congress that I thought were patently unfair," he said. "Because these [were the] same members of Congress who were briefed on this program when it was first initiated. They had no objection to waterboarding or other enhanced techniques from the get-go. ... As somebody who was involved in the counterterrorism center at the time, I resented it. So I decided, against the advice of a lot of friends of mine, that I was going to say something."

The debate of interrogation practices is healthy and necessary, Mr. Kiriakou said, if America is to regain the moral high ground it sacrificed in the days after Sept. 11, when the priority of punishing those responsible and preventing further attacks resulted in some questionable compromises.

"You can't launch an intelligence operation based on anger or revenge. It has to be clearheaded with an end goal of keeping the country safe," he said. "The only way to regain [the moral high ground] is to allow time to pass, to turn our backs on these enhanced techniques, and to try to start fresh. Maybe with a new administration, regardless of which party wins."

Mr. Kiriakou said he was always conflicted about the techniques. But the CIA did not address issues of morals and ethics when instructing new operatives. The focus instead was on intelligence-gathering techniques and the jobs at hand.

Now, he said, it's time to re-evaluate.

"We had our very limited window to play dirty," he said. "And the window has to close."