Gregory Francis Zoeller (born March 28, 1955) is an American lawyer who served as the 42nd attorney general of the U.S. state of Indiana from 2009 to 2017.

[1][2] He supported needle exchange programs and the deployment of naloxone (Narcan) in order to minimize harms (such as HIV and hepatitis C) caused by intravenous drug use.

[9][10] Zoeller also joined lawsuits challenging Obama administration EPA environmental protection regulation, including a water pollution rule and the Clean Power Plan.

"[18] In 2016, Zoeller sought the Republican nomination primary election for Indiana's 9th congressional district, a seat in the U.S. House of Representatives, but was defeated by millionaire businessman Trey Hollingsworth.

[8][4] Shortly after leaving office, he donated $10,000 in remaining campaign funds to the Indiana Bar Foundation, saying that the contribution "concludes my public service.

"[19] He made plans to teach part-time at a law school, work as a mediator, and pursue business endeavors, adding, "I don't know if I fit today's political arena.

[3][8] In 2020, he described himself as a "former Republican" in presidential elections (saying "it's abundantly clear that the GOP is not likely to return to the party I joined anytime soon") and he voted for Democrat Joe Biden in 2020.