Kevin D. Williamson has penned an article at the National Review called "Meet the New Serfs: You." The article discusses how as citizens face increasing amounts of bureaucratic red tape--and consequences for even minor mistakes--government bureaucrats seem to be completely unaccountable for their screw-ups. Most of the article focuses on incidents of no-knock warrants, but it applies to other levels of the bureaucracy. Williamson does not attempt to address how this situation came about, but it is simple to figure it out: and both are due to progressive "reforms."
First was the institution of a so-called professional bureaucracy to replace the traditional spoils system. The alleged purpose of this was to reform the corruption inherent in political machines by making the selection of public employees a matter of merit rather than cronyism. In fact, the only impact it had was to insulate bureaucrats from the wrath of the electorate, and shift the cronyism from the political boss to the bureaucratic boss.
Second, which was the final nail, was the determination by the Supreme Court (the ultimate unanswerable bureaucrats) that public employment was a "property right" that could only be taken away after the employee was afforded "due process"--i.e., a hearing and right to present evidence. Basically, it largely eliminated "at-will" employment for public employees, making it even more difficult to get rid of the bad ones. Of course, this was worsened by the creation and spread of public employment unions.
As you can see, however corrupt public employment was before, at least a politician afraid of losing an election if he didn't do something about incompetent or abusive employees could at least fire those employees. A switch in controlling parties could result in real change if enough public employees lost their jobs. However, that is not possible now. The bureaucracy is the real government, and voting is largely an exercise in futility.