Because the police, over time, have put laws in place to protect their jobs even in the case of severe abuse. Why do you think the POA (Police/"Peace" Officers Association) goes around endorsing/attacking local political candidates?
Consider the shootings in Albuquerque. 26 people killed by ABQ cops in the last few years; and not a single officer held accountable. Even when there's unambiguous police video of abuse!
http://www.slate.com/blogs/the_slatest/2014/06/20/albuquerqu...
The amount of process due is largely determined by case law, with judges using a balancing test that balances several factors.
Most to the point in your hypo, one of the factors is the government interest involved.
The government has a much stronger interest in detaining a possible flight risk and processing you through the criminal system than in suspending an officer's pay before some sort of notice and a hearing is given.
Police officers can be flight risks. One of the "riders" from Oakland is still at large.
Bullshit. The police can throw me in jail before a trial, preventing me from going to work. How's that not a violation of due process?
>It's probably unconstitutional to impose forfeiture of vested interests as punishment for a crime.
True. You could sue them for enough that they could no longer make the payments on their house, though.