In 1966, Carroll ran for one of Hawaii's two at-large congressional district seats; he came in third behind incumbents Patsy Mink and Spark Matsunaga.
[6][7][8] On August 17, 1970, Carroll announced that he would seek the Republican nomination for one of three 12th state house district seats; he came in first, ahead of five other candidates.
He also proposed a bill (later defeated) that would allow for the recalling of elected officials and a Castle doctrine amendment to Hawaii's penal code.
[27][28] During his tenure he served on the Judiciary, Agriculture, Economic Development, Consumer Protection and Commerce, and Government, Operations and Efficiency committees.
He was against Hawaii's expansion of its fishing industry; he and asked Governor George Ariyoshi to ban lobster harvesting along the Leeward Islands, and voted against a resolution supporting the District of Columbia Delegate Act.
[29][30][31][32] The 6th District was redistricted from four seats down to two; in the 1980 election, both incumbents, John Carroll and Anson Chong, narrowly lost reelection.
[37][38] He ran campaign ads that opened with, "Aloha, I'm John Carroll, and in no way am I a racist;" in the general election, he lost to Akaka.
On May 27, 2009, he announced that he would challenge Lieutenant Governor Duke Aiona in the Republican gubernatorial primary, but received less than 5% of the vote.
[42] On September 21, 2011, he announced that he would run for the Republican nomination for Senate against Linda Lingle; he campaigned against the Jones Act and a Native Hawaiian federal recognition bill.
[43] In the primary, he was again defeated by Lingle (she took over 90% of the vote); Carroll later endorsed Democratic Representative Mazie Hirono in the general election.
In mid-March, Carroll was leading state House Minority Leader Andria Tupola in the Honolulu Star-Advertiser's statewide poll of likely 2018 Republican voters by a margin of 12 percentage points, with 40% of potential Republican voters supporting Carroll as opposed to 28% supporting Tupola.