I've watched the xfiles more times than I like to admit, but something I've always wondered about is why are the cops/police/sheriffs such assholes?

One thing to add to what others have said but when the feds show up they don't just take over an investigation in real life. They always show in TV/Movies about feds coming and taking over but it isn't true.

In reality the FBI shows up and HELPS local/state police. They pool their efforts together. They work together. They don't just take over an investigation and leave the local/state police to do nothing. Local/state police are not subordinates to the FBI and the FBI does not supervise or take over investigations.

Source

/r/XFiles Thread