Diaz practiced law on the Gulf Coast He served in the Mississippi House of Representatives from District 116 representing Biloxi and DIberville for seven years from 1988 to 1994 During his tenure in the Legislature he was a subcommittee Chairman for the Insurance Committee and for the Judiciary Committee He was on the Ways and Means Committee and was Secretary for the Constitution Committee He also served as City Attorney for the City of DIberville for four years Justice Diaz was elected to the Court of Appeals in November 1994 and served in that position until March 2000 at which time he was appointed to the Supreme Court by Governor Ronnie Musgrove In 2000 he was elected to the Supreme Court for an eight year term beginning January 2001