The police can sell property for funding. A convoluted process for recovering property increases demand for law services, so even though defense attorneys might be against the process ethically, they still stand to gain from the process financially. The DA wants to have as many power levers as possible. The courts collect fees to file a motion.

It sounds like money, as well as probably being able to screw someone over they don't like.

Tough on crime..

Aren't most of these politically elected or appointed?

In many other countries the police chief, DA and judges are independent or their appointment has many levels of indirection.