Red-Ear Sliders are listed by the state of Florida as a Conditional Nonnative Species. Due to their previous sale in many pet stores across the state, and their large amount of care and expense required for upkeep, people found themselves unable to properly house these turtles and ended up releasing them into the wild.
The problem with that is many-fold. First of all, most sliders you would buy at a pet store will more than likely not live past 6 months of age anyways. Wild release means that you are taking a hand-fed fragile baby--used to you giving them feed pellets--and dropping them off into the great unknown with zero survival skills.
If by some miracle the baby or adolescent survived to maturity, the next problem you have created is adding a nonnative species in with native species that they are able to reproduce with. Red ear sliders have reproduced with yellow belly sliders (a native Floridian) creating a species problem there as well.
As of July 2007, nobody in the state of Florida may sell Red Ear Sliders. Further, keeping these guys in this state requires immediate euthanasia of babies, surrender to certified rescue organizations of turtles under 4" as of July 2008, or immediate destruction of any laid eggs should your pets decide to procreate. This is the law.

