Mississippi Code Title 99. Criminal Procedure § 99-19-1

No statutory change of any law affecting a crime or its punishment or the collection of a penalty shall affect or defeat the prosecution of any crime committed prior to its enactment, or the collection of any penalty, whether such prosecution be instituted before or after such enactment; and all laws defining a crime or prescribing its punishment, or for the imposition of penalties, shall be continued in operation for the purpose of providing punishment for crimes committed under them, and for collection of such penalties, notwithstanding amendatory or repealing statutes, unless otherwise specially provided in such statutes.