Parker was born in Laurel, Mississippi and he graduated from William Carey College with a BA in English in 1970. Before politics, Parker owned and operated a homes, insurance companies, land and timber companies, and a sand, clay and gravel business. Parker was elected to the House of Representatives as a Democrat in 1988. During his election campaign, he refused to endorse Democratic party Presidential candidate Michael Dukakis. Parker faced a primary challenge in 1994. Parker voted 'Present' in the election for Speaker of the House in 1995 instead of voting for the House Democrat leader Richard Gephardt.

In November 1995, Parker joined the Republican Party. Parker easily won re-election in 1996 and refused to run for re-election in 1998. Parker ran for Governor of Mississippi in 1999 against Ronnie Musgrove. Parker had almost 9,000 fewer votes than Musgrove, but Musgrove didn't have a majority of the popular vote and he didn't have a majority of the state electoral votes (based on State house districts). The Mississippi House of Representatives elected Musgrove governor by an 86-36 vote.

Parker was appointed by George W. Bush as Assistant Secretary of the Army (Civil Works), with oversight of the Army Corps of Engineers (despite never having studied or practiced engineering) but was later asked to resign.