Carroll was born in Port of Spain, Trinidad and Tobago. She moved to the United States at the age of eight, and graduated from Uniondale High School in Uniondale, Long Island New York in 1977. She enlisted in the U.S. Navy in 1979. After serving as an aviation machinist’s mate (jet engine mechanic), she was selected for the Enlisted Commissioning Program, becoming an Aviation Maintenance Duty Officer in 1985. She retired from the U.S. Navy in 1999 as a lieutenant commander.

In 1981, she received an Associate of Arts degree from Leeward Community College. She followed this in 1985 with a Bachelor of Arts in political science from the University of New Mexico. She moved to Florida in 1986. She received a Master of Business Administration degree from unaccredited and now defunct Kensington University in 1995. Carroll resigned her position on the National Commission of Presidential Scholars to accept a presidential appointment to the Veterans’ Disability Benefits Commission. She then returned to school to earn an accredited Master of Business Administration degree online from St. Leo University in 2008.

Following the 2000 elections, Carroll was appointed Executive Director of the Florida Department of Veterans Affairs by Republican Governor Jeb Bush and served in that post until July 2002. Republican President George W. Bush appointed Carroll to the Commission on Presidential Scholars from 2001 to 2004, and then a seat on the Veterans’ Disability Benefits Commission from 2004 to 2007.

Carroll is a member of the Clay County Republican Executive Committee. In 2000, she ran for a seat in the U.S. House of Representatives in the Florida’s 3rd congressional district. Incumbent Democratic U.S. Congresswoman Corrine Brown defeated Carroll 58%–42%. After redistricting, she ran for a rematch against Brown in the newly redrawn 3rd district in 2002. Brown defeated her 59%–41%.

Carroll ran for a seat Florida House of Representatives in the 13th state House district after incumbent State Representative Mike Hogan, also a Republican, resigned in 2003. In the April 2003 special election, she won the Republican primary with 65.5 percent of the vote, defeating Linda Sparks, who won 34.5 percent of the vote. She became the first Black female Republican ever elected to the Florida Legislature. She won unopposed in 2004, 2006, and 2008.

On November 2, 2010, the Republican ticket of Rick Scott and Jennifer Carroll defeated the Democratic ticket of Alex Sink and Rod Smith, 48.9%–47.7%. The first black person, the first woman, and the first Trinidadian American elected to the position, she assumed the office on January 4, 2011. Carroll was the first black Republican elected to statewide office in Florida since Reconstruction.

Carroll came under further scrutiny for public relations work for a charity that involved itself in illegal online gambling and for $24,000 in income which she failed to report on disclosures and tax returns. Though the Ethics Committee found no evidence of wrong doing, at the request of Governor Rick Scott, Carroll resigned her post as lieutenant governor on March 12, 2013. The Florida Department of Law Enforcement subsequently concluded that she did not break any laws.

After working on the 2016 presidential campaign on behalf of Donald Trump, Carroll was appointed by President Donald J. Trump as a Commissioner on the American Battle Monuments Commission. Carroll has served on the Commission since April 2018.