"He's held no one accountable," Cornyn told "Fox and Friends."
Tuesday's Senate Judiciary Committee hearing was the first congressional hearing since memos revealed Holder's office knew early on about the botched ATF operation. Republicans have called for Holder's resignation since the memos were uncovered, and Cornyn, among others, grilled the attorney general.
“I have not apologized to them, but I certainly regret what happened,” Holder said at the hearing.
However, he also pushed back against faulting the operation for Terry's death.
“It pains me whenever there is the death of a law enforcement official, especially under the circumstances,” Holder said. "It is not fair, however, to assume that the mistakes that happened in Fast and Furious directly led to the death of Agent Terry."
Cornyn kept pushing Holder on Terry at the hearing. "I was trying to give him an opportunity to do the right thing," he said on FOX. "He declined."
Cornyn said he still has a lot of questions about the operation, saying he is not sure yet whether Holder is "intentionally" misleading Congress or is simply ignorant of what takes place within the agency.
"I'm not sure which is worse," he added. "[Holder is] not a stupid man, he's an intelligent man, and he should know better."
Holder told the committee that the the controversial gun-tracking operation was "flawed" in concept and execution. "This should never have happened. And it must never happen again," the atorney general said.