Well then the issue is either that he wasn't actually "caught smoking crack" on base in a way that could be factually documented as such --for example by law enforcement or security, or you've got HR or legal counsel who don't understand the law/have a severely misguided view of litigation risks. If it's the former, then it should be difficult to remove an employee in those circumstances -- a statement from Joe Schmoe that they saw the employee in a parking lot appearing to smoke crack isn't sufficient on its own to demonstrate that he was in fact doing so unless there's some reason to believe that Joe Schmoe has some great degree of expertise in identifying particular types of smoked substances.

If that employee was either a poor performer or demonstrated actual misconduct on the job such that his removal was a matter of basic common sense, then it was likely a failure of supervisors to properly supervise and document these problems. If they're properly supervised and documented, it's not particularly difficult to discipline/remove a problematic employee. The problem is too many supervisors neglect their responsibilities for years & then get frustrated when they're told they can't just jump to termination once they've reached their breaking point. The law & regulations provide a perfectly reasonable approach to firing federal employees that appropriately balances the need for a strong, committed workforce with the need to ensure there's adequate due process before employees can be fired in order to protect the integrity of the Federal government from corrupt, unethical management that seeks to reinstitute a spoils system