[1] The Office of Legal Counsel was created in 1934 by an act of Congress, as part of a larger reorganization of executive branch administrative agencies.

This name was changed to Office of Legal Counsel in an administrative order by attorney general Herbert Brownell Jr., issued April 3, 1953.

According to press accounts, OLC has historically acted as a referee within the executive branch and its legal opinions have generally been given deference among the agencies and departments.

These memos advised the CIA and the Department of Defense that the president may lawfully authorize the torture of detainees (euphemistically referred to as "enhanced interrogation techniques"), including beating, binding in contorted stress positions, hooding, subjection to deafening noise, sleep disruption,[6] sleep deprivation to the point of hallucination, deprivation of food, drink, and withholding medical care for wounds, as well as waterboarding, walling, sexual humiliation, subjection to extreme heat or extreme cold, and confinement in small, coffin-like boxes.

[13][14][15] An opinion issued by the Government Accountability Office concluded that his status was not a violation of the Federal Vacancies Reform Act of 1998.

[17] In 2009, attorney general Eric Holder overturned an unpublished OLC opinion that had concluded that a D.C. voting rights bill pending in Congress was unconstitutional.

[18] Early in the Trump administration, OLC approved Executive Order 13769 (referred to as the "travel ban" because it restricted entry from certain foreign countries which had Muslim-majority populations).

[20] In a United States Senate hearing, Yates was asked whether she was aware of any past instance of an attorney general rejecting an executive order that had been approved by OLC.

[22][23][24] This memorandum was written in tandem with the Barr letter over the course of two days;[25] the final version was signed by Steven Engel and Ed O'Callaghan.