Pros
Job security, reliable pay. If you can get on with the state, you'll likely have a job for as long as you want it, even if you're an employee that most employers would fire. While this is good for bad employees, it also leads to an environment where a small percentage of conscientious employees must do the work of ten employees without appreciation, at the same pay as the bad workers.
Cons
Extremely low salary, worst morale of anywhere I've ever worked...and I worked in fast food as a teen. The hard workers get a pay raise at the same time as the lazy employees. The laughably bad pay is gradually leading to an environment full of workers who can't get jobs elsewhere, along with a few who are there because of the benefits and don't need money (spouses work in private sector). For career-minded people who want to do something with their lives, I would recommend working anywhere but in government. Government jobs were good in the 1950s--seek out a progressive large company if you want security...at least they care about retaining good employees.