The United States initially established an Attorney General as a one-person, part-time job with the Judiciary Act of 1789.
At one time, the Attorney General gave legal advice to the U.S. Congress as well as the President, but this practice had stopped by 1819 on account of the growing bureaucracy.
Then in 1867, the U.S. House Committee on the Judiciary, led by Congressman William Lawrence, conducted an inquiry into the creation of a “law department” headed by the Attorney General and composed of the various department solicitors and United States attorneys.
On February 19, 1868, William Lawrence introduced a bill in Congress to create the Department of Justice. This first bill was unsuccessful, however, as Lawrence could not devote enough time to ensure its passage owing to his occupation with the Impeachment of President Andrew Johnson.
A second bill was introduced to Congress by Rhode Island Representative Thomas Jenckes on February 25, 1870, and both the Senate and House passed the bill. Jenckes was also an avid supporter of civil service reform.
President Ulysses S. Grant then signed the bill into law on June 22, 1870.
The United States Department of Justice officially began operations on July 1, 1870.
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