In Louisiana, we have something called a “cleansing period” that applies in cases of multiple DWIs. This cleansing period begins after a DWI conviction or plea, and ends 10 years after that date. Once this cleansing period passes, past pleas or convictions cannot be used against you in order to enhance further DWI charges. However, keep in mind that a 2008 law extends this 10 year window to exclude the time between your arrest and your probation time.