The state Supreme Court has rejected the appeal of Anthony Brown's attorney.
Last year, a jury convicted Brown and he was sentenced to life behind bars plus five years.
The court affidavit says Brown doused his girlfriend, Veronica Norwood, with gasoline when she returned to their trailer to pick-up her belongings. Brown then lit a paper towel on a hot plate and threw it on her. Norwood was airlifted to a hospital in Gainesville, where she stayed for eight months. She died from breathing troubles shortly after her release.