New Secretary of Homeland Security Michael Chertoff was sworn into office Tuesday, Feb. 15, after his nomination was approved by the U.S. Senate.

The Homeland Security Department includes the Transportation Security Administration, which oversees a number of security related issues in the trucking industry.

Formerly a judge for the U.S. Third Circuit Court of Appeals, Chertoff previously served as assistant attorney general for the Criminal Division at the Department of Justice, where he helped trace the Sept. 11, 2001, terrorist attacks to the al-Qaida network, according to a news release from the Homeland Security Department. He also worked to increase information sharing within the FBI and with state and local officials.

President George W. Bush announced Chertoff’s nomination Jan. 11 at the White House with Chertoff at his side.

Chertoff replaces Tom Ridge, who founded the department after it was created in the wake of the attacks. Ridge, a former Pennsylvania governor, oversaw what many observers describe as the largest reorganization in the federal government since the creation of the Department of Defense after World War II.