(CNN) -- The Justice Department has decided it won't referee charges -- and countercharges -- of spying between the CIA and the Senate Intelligence Committee.
The CIA's general counsel and inspector general each made criminal referrals to the Justice Department seeking an investigation of whether Senate staffers obtained unauthorized access to classified documents related to the agency's now-defunct post-9/11 interrogation program.
Soon after, Senate Intelligence Committee Chairman Dianne Feinstein went to the Senate floor to accuse the agency of spying on computers used by committee staffers at a CIA facility to investigate the Bush-era interrogation program.
Now, the Justice Department has notified the CIA and the Senate committee that it can't find enough evidence to warrant a full-blown probe.
"The department carefully reviewed the matters referred to us and did not find sufficient evidence to warrant a criminal investigation," Justice Department spokesman Peter Carr said.
The CIA declined comment. Feinstein's office didn't immediately comment.
Critical report on CIA
The unusual dispute has raised tensions between the agency and lawmakers charged with overseeing its activities.
The committee has produced a 6,300-page report on the program, which critics say violated prohibitions on torture and exceeded legal guidance from the Justice Department.
The White House and the CIA are reviewing an executive summary of the report to remove classified information before it can be released.
The documents that prompted the dispute relate to an internal review by former CIA Director Leon Panetta and, according to the agency, were intended to help summarize material it was providing to the committee for its investigation of the program.
The documents were plainly labeled as for internal use and were not supposed to be reviewed by the committee, according to the CIA.
Feinstein said Senate staffers found the documents in the course of their work that were put in the computer system either on purpose by a whistleblower or perhaps in error, and that they corroborated some of the committee's findings that the agency now says it disagrees with.
She said committee staff routinely sees such documents and didn't violate any classified restrictions.
Senate Majority Leader Harry Reid said Thursday he believes the Senate has handled the matter appropriately.
"I think what the CIA did to my senators is wrong. I'm going to drop it at that," Reid said.
Democratic Sen. Mark Udall of Colorado said, "I still believe the CIA's entry into our computers was unacceptable perhaps even unconstitutional and we shouldn't let this drop until we have some sort of fundamental resolution of what happened. This wasn't the first time this occurred and the division of powers in our nation's constitution is at some risk here."
Udall said it's time for the White House and the CIA to release the portions of the Senate's report under review.
Feinstein is usually one of the intelligence community's staunchest allies in Congress.
CIA says it acted properly
CIA Director John Brennan has disputed Feinstein's accusations of agency wrongdoing in uncovering Senate staff access to the internal report.
Speaking to the Council on Foreign Relations in March, he said, "when the facts come out on this, I think a lot of people who are claiming that there has been this tremendous sort of spying and monitoring and hacking will be proved wrong."
Dean Boyd, a CIA spokesman, said in an op-ed published in USA Today in March that the agency acted properly after it discovered Senate staffers may have accessed and retained sensitive documents stored in a CIA computer network.
"These documents were privileged, deliberative, pre-decisional executive branch material that implicated separation of powers concerns," Boyd wrote. "Because we were concerned that there may have been a breach or vulnerability in the CIA local area network on which CIA stored these documents, CIA information technology specialists were asked to conduct a limited review to determine whether these files were located on the side of the CIA network the committee was authorized to use. That review appeared to confirm the committee's unauthorized access to the documents."