"If the record shows that Haspel played any role in carrying out, supervising, or directing any form of torture or detainee abuse, or the destruction of evidence relating to these activities, we urge you to reject her nomination," the letter said.
The letter cited reports that Haspel ran a CIA "black site" in Thailand at which at least one detainee, Abd al-Rahim al-Nashiri, was repeatedly tortured by waterboarding and she oversaw the process.
READ MORE: 'Acted Appropriately': CIA Memo Says Haspel Was Right to Destroy Torture Tapes
The letter did note that US officials have highlighted Haspel’s rich experience and long record of excellent service to CIA.
"However, we do not accept efforts to excuse her actions relating to torture and other unlawful abuse of detainees by offering that she was 'just following orders,' or that shock from the 9/11 terrorist attacks should excuse illegal and unethical conduct," the retired officers said.
The US Justice Department investigated the destruction of the tapes, but did not file charges
Haspel’s nomination has been publicly supported by some lawmakers, including Senator Dianne Feinstein, who headed a Senate committee that released a report on CIA’s torture practices. Feinstein told reporters in March that Haspel was a good deputy director of the CIA and said she hoped the agency learned its lessons.