DOJ releases details of probe into origins of Russia investigation

"The Review is broad in scope and multifaceted, and is intended to illuminate open questions regarding the activities of U.S. and foreign surveillance services as well as non-governmental organizations and individuals."

The big picture: Trump has granted Attorney General Bill Barr the authority to unilaterally declassify any information he chooses as he investigates whether the U.S. intelligence community improperly surveilled the Trump campaign leading up to the 2016 election. The U.S. Attorney for the District of Connecticut John Durham has been appointed to lead the investigation.

Between the lines: The language in the letter is likely to intended to mitigate some of the fears about Barr's new declassification powers, stressing that DOJ will work closely with the intelligence community to protect sources and methods.

• Notably, the letter does not mention the term "spying," which Barr and many Trump allies have used when discussing surveillance of the campaign — language that has prompted significant backlash from Democrats and some national security officials. Instead, DOJ refers to "intelligence-gathering and investigative steps directed at persons associated with the Trump campaign."

Go deeper: What the Mueller report tells us about Trump and Russia