Every once in awhile, the CIA gets its hands on a hard drive just full of data on American citizens, including millions of pages of text, videos and large amounts of photographs. So irrespective of long-standing prohibitions on the CIA spying on American citizens (apart from some very limited exceptions) they obviously are going to go through those documents.
Today, the CIA released a declassified version of the procedures for handling the private data of American citizens. Unsurprisingly, this leaves open a lot of questions, with a lot of the rules detailing the minutia of the manner in which they search bulk data.
The main talking point, which the CIA presented as a “significant step,” is that it defines actually which CIA employees are allowed to conduct searches of the bulk data they have, and that they actually need “a reason” to justify carrying out such a search.
These rules are all purely hypothetical at any rate, since CIA operations within the US are wholly guided by a presidential order from 1981, which more or less precludes courts getting directly involved in such actions, even if the CIA ends up openly flouting its own rules.