For example, the report stated as fact that Mr. Snowden stole 1.5 million documents, a “vast majority” of which “were unrelated to electronic surveillance or any issues associated with privacy and civil liberties.” The notion that he took all those files to Hong Kong is a foundational premise for more alarming interpretations of his actions.

However, intelligence officials have said that the government was unable to determine which files he took, and that the 1.5 million figure was based on how many files were “touched” by an indexing program that Mr. Snowden used to trawl N.S.A. servers. The unredacted portions of the report do not indicate whether the panel learned anything new to clear up that murkiness.

Still, the report offered some new information about Mr. Snowden’s actions leading to the leaks, including descriptions of episodes in which he tussled with various supervisors.

The report described a June 2012 clash in which Mr. Snowden, then a Dell contractor working as a systems administrator at the N.S.A.’s outpost in Hawaii, uploaded a patch to fix a security vulnerability on a set of servers, which then crashed. A middle manager sent a group email chastising him for not having tested it first.

In a reply email in which Mr. Snowden copied a senior manager in Washington, the report said, he accused the middle manager of focusing on “evasion and finger-pointing rather than problem resolution.” The senior manager sharply rebuked Mr. Snowden, replying that under “no circumstances will any contractor call out or point fingers at any government manager whether you agree with their handling of an issue or not.”

The report portrayed this episode as potential motivation for Mr. Snowden’s decision to begin illicitly copying documents, which it said he started just a few weeks later, on July 12, 2012. It contrasted that timeline with Mr. Snowden’s later statement that “the breaking point” was false testimony by James R. Clapper Jr., the director of national intelligence, in March 2013.