McCarthy was born in New Jersey and moved to Brevard County, Florida with his family in 1979 at the age of eleven.
In Berlin, he was the youngest battalion staff level fire support officer in the United States military.
Afterward, he worked in medical license regulation for the state of Florida, and then in employment and civil rights law.
[13] Arguing against Christian versus Muslim sentiments in the case, McCarthy tried to dispel the perception that the parents were fundamentalists.
[15] McCarthy successfully ran for and served on the board of the Ochlockonee River Soil and Water Conservation District while living in Leon County, Florida.
He ran for the Florida House of Representatives out of District 36, against incumbent Scott Randolph,[16] receiving early support from Conservatives.
[17] He, along with local Tea Party leaders and politicians, drove in a caravan to Arizona to support its immigration law, claiming selective immigration enforcement is uncompassionate and causes people to live in fear, and that the federal government has failed in its duties to protect the people of Arizona.