William Joseph Baer (born May 31, 1950)[1] is an American lawyer who served as the Assistant Attorney General for the United States Department of Justice Antitrust Division under the administration of President Barack Obama.

[3] Upon graduating law school in 1975, Baer took a job with the Federal Trade Commission (FTC) where he held positions as Assistant General Counsel and Director of Congressional Relations; Attorney Advisor to the Chairman; Assistant to the Director, Bureau of Consumer Protection; and Trial Attorney, Bureau of Consumer Protection.

[3] During his work at Arnold & Porter, Baer's clientele included Monsanto, General Electric, Intel, Micron Technology, and Cisco Systems.

[citation needed] On February 6, 2012, President Obama nominated Baer to serve as Assistant Attorney General for the Antitrust Division, filling the slot vacated by Christine A.

[9] On March 1, 2016, Baer filed an Antitrust Division indictment against oilman Aubrey McClendon alleging conspiracy to fix bidding on freehold oil and natural gas leases.

[10] The following day, McClendon drove his vehicle at high speed into a bridge embankment in Oklahoma City and died instantly in what the police ruled an accidental death.