The Justice Department on Friday turned over to Congress nearly 1,400 pages of “highly deliberative internal communications” about the drafting of a February letter in an effort to show that agency officials did not knowingly mislead lawmakers in connection with a disputed gun trafficking investigation called Operation Fast and Furious.

The letter, which rejected early accusations of wrongdoing in Fast and Furious, told lawmakers that the Bureau of Alcohol, Tobacco, Firearms and Explosives “makes every effort to interdict weapons that have been purchased illegally and prevent their transportation to Mexico.