[3] In 1976, he founded Gregg Industrial Insulators, Inc.[5] It was admitted to the OSHA, Voluntary Protection Program,[5] [1] and is a multi-million dollar company[6] which employs more than five hundred workers.

[5] From 1986 to 1993 Merritt served as one of the directors of the Gregg County Appraisal Board, which led to his appointment by Governor Bill Clements to the Sabine River Authority in 1990.

In 2009, Merritt authored "campus carry" legislation allowing concealed handgun license holders to carry their weapons on college campuses,[10] while in 2007, Merritt authored legislation waiving or reducing concealed license handgun fees for military members and veterans.

[16] While a member of the Texas House, Merritt also strongly opposed abortion, co-authoring bills to issue Choose Life license plates in 2009,[17] to institute legal penalties for harm to a fetus in 2003,[18] to ban human cloning in 2007,[19] and to require parental consent for minors to obtain abortions in 2005.

[28] That same year, he co-authored a proposed constitutional amendment requiring a 2/3 vote of both houses of the Legislature to raise taxes.

[34] Merritt also authored or co-authored numerous bills to overturn and subsequently prohibit inheritance taxes in Texas in 2005[35][36] and 2003.

Meanwhile, Simpson, who beat back Merritt's attempt in 2012 to return to the House, was a candidate in January 2013 for Speaker of the Texas House of Representatives against Joe Straus of San Antionio, whom Merritt had supported in 2009, when Straus ousted the previous Republican speaker, Tom Craddick of Midland.