WASHINGTON — Gina Haspel’s long spy career is so shrouded in mystery that senators want documents declassified so they can decide if her role at a CIA “black site” should prevent her from directing the agency.

It’s a deep dive into Haspel’s past that reflects key questions about her future: Would she support President Donald Trump if he tried to reinstate waterboarding and, in his words, “a lot worse”? Is Haspel the right person to lead the CIA at a time of escalating Russian aggression and ongoing extremist threats?

Haspel’s upcoming confirmation hearing will be focused on the time she spent supervising a secret prison in Thailand. The CIA won’t say when in 2002 Haspel was there, but at various times that year interrogators at the site sought to make terror suspects talk by slamming them against walls, keeping them from sleeping, holding them in coffin-sized boxes and forcing water down their throats — a technique called waterboarding.

Haspel also is accused of drafting a memo calling for the destruction of 92 videotapes of interrogation sessions. Their destruction in 2005 prompted a lengthy Justice Department investigation that ended without charges.

“We should not be asked to confirm a nominee whose background cannot be publicly discussed and who cannot then be held accountable for her actions,” said Sen. Martin Heinrich, who joined other Democrats on the Senate intelligence committee in asking the CIA to declassify more details about Haspel.

Court filings, declassified documents and books written by those involved in the CIA’s now-defunct interrogation program suggest Haspel didn’t arrive at the secret prison in Thailand until after one detainee, Abu Zubaydah, was waterboarded 83 times in August 2002. But they indicate she arrived before another detainee, Abd al Rahim al-Nashiri, was waterboarded at least three times in November 2002.

Even if Haspel was at the prison site for just a few months, Steven Watt, an American Civil Liberties Union attorney, said she was deeply involved in the interrogation program. For much of its existence, Haspel was deputy director of the CIA’s counterterrorism center that ran the program using “enhanced interrogation techniques.”

At least 119 men were detained and interrogated as part of the program, said Watt, who represented two detainees and the family of another in a 2015 lawsuit against a pair of CIA-hired psychologists.

Several colleagues and former intelligence officials have come to Haspel’s defense. Mike Morell, who was an acting director of the CIA, worked closely with Haspel from 2006 until he retired in 2013. Morell has described her as a person who gets things done in a “quiet, yet effective way” and is “calm under fire.”

“The media is also likely to refer to a moment in her career when she drafted a cable instructing a field station to destroy videotapes of CIA interrogations of senior al-Qaida operatives,” Morell wrote when Haspel became deputy CIA director last year. “She did so at the request of her direct supervisor and believing that it was lawful to do so.”

And former CIA spokesman Bill Harlow said the focus on interrogation obscures the CIA director’s wide-ranging portfolio. Instead of re-litigating the past, he said Haspel should be asked about Russia, China and cyber threats and how to improve intelligence collection on U.S. adversaries.

Ret. Air Force Col. Steven Kleinman, a longtime interrogator, isn’t sure. He said he doesn’t know Haspel’s views on the harsh interrogations, but said there’s no indication she ever tried to halt them.

“That question has to be asked by the Senate: ‘Did you at any time suggest that it be stopped because it’s ineffective, immoral or illegal?’?” Kleinman said. “I think we all deserve an answer to that.”