A federal judge has struck down a Florida drug law that convicts suspects of a drug offense even if they are unaware that the controlled substance is illegal.

U.S. District Judge Mary Scriven found the 9-year-old law unconstitutional in a decision Wednesday and called for the resentencing of Mackle Shelton, who had faced 18 years in prison.

The ruling could pave the way for drug cases currently in the courts to be thrown out.

"Obviously, we are immediately drafting motions and pursuing this line on behalf of our own clients' (cases) that are pending, but we can't do much retroactively since those cases are closed," said Bob Wesley, public defender for Orange and Osceola counties. "I think it will be a robust line of litigation for all of us who appear in Florida criminal courts."

Tampa attorney James Felman, who won the landmark case, says the Florida legislature went too far.

"What the legislature attempted to do was essentially presume guilt and then let you come in and prove your innocence if you wish to avoid being imprisoned," Felman told MyFoxTampaBay.com.

When the law was passed in 2002, Florida became the only state not to require that a suspect have knowledge that a controlled substance is illegal to be convicted. The law shifted the burden from prosecutors having to prove that a suspect knew to the defendant having to assert ignorance about the illegality of the controlled substance.

Attorney General Pam Bondi's office says they are currently reviewing the case. Many thing the state will appeal the decision.

Click here for more on this story from MyFoxTampaBay.com.

Florida drug law ruled unconstitutional: MyFoxTAMPABAY.com

The Associated Press contributed to this report.