Life-time bans for althletes don't fit the crime, undoes the organization that bans them is completely free from government influence and control. Of course, if an athletic organization uses coercion to prevent an athlete so "convicted" from participating in the sport at all (including outsode the league or governing body), then I oppose such power.
As terrible as drugs are, I do not believe the use of them should lead an athlete to a lifetime ban of participating in sports. We all make mistakes. We all deserve a second chance. Now, when you start getting into third, fourth, and fifth chances, that gets to be a bit much as a line needs to be drawn somewhere.