According to reports, the document critiques the government's legal rationale for the NSA program, Section 215 of the Patriot Act. It also questions the utility of the program, looking closely at some investigations where it was used and saying that there was "no instance in which the program directly contributed to the discovery of a previously unknown terrorist plot or the disruption of a terrorist attack."
The report recommends that raw phone records be deleted after three years rather than five, and the access to search results be limited further.
In a speech last week, President Barack Obama said he was ordering curbs on the use of such mass data. But he said the US must continue collecting data to prevent attacks.