1. If he/she feels their life or anyone involved in the situation is in danger of injury/death. Just because he is a police officer doesn't mean he has to give anyone any more of an opportunity to harm them than a private citizen. Yes, I should hold myself to the same standard...I'm sure the legal system would. No new laws.
2. I don't think the system is racist...there are racist people in the system, but that is in any "system", sadly.
3. I don't know...let the facts come out.