How about putting aside complaints about a system that makes it difficult to fire an employee that does not perform......just for a minute?
As a senior HR Manager/Professional, I cannot tell you how many times I've heard this unsubstantiated complaint from managers. Can it be difficult? Yes! MUST it be difficult? NO!
The problems managers encounter when trying to remove an employee are usually created by the manager or his or her predecessor. Removing an employee is not completely unlike sending a citizen to jail; A case must be proven and that means that management must have their stuff in order and nine times out of ten, this is normally where the problem lies.
So my recommendation as to how to address the performance problem in government is to hold the manager accountable for EVERY employee failure; if an employee is not consistently performing, neither is the supervisor.....simple as that!!
Do your job as a manager. Record, counsel and discipline! Along with the technical responsibilities, THIS IS YOUR JOB, OWN IT OR MOVE ON!