I don't agree. Government employees' lives aren't more valuable or important than anyone else's.
It has nothing to do with perceived value of life. It has to do with the fact that Govt Employees PUT THEIR LIVES ON THE LINE far more often than you do. FBI, Secret Service, Federal Investigators, TSA, are all out there to keep you safe. They place their lives in harm’s way, to protect you. The idea is to make the criminal think twice before killing them; so they can go home to their families after work, just like you.