The police are trained so when a truck starts ramming against a police vehicle without stopping, they make it stop. When the police officer’s life could pretty much be in danger, they’ll kill you. Duh.
Yeah, if someone is in a large vehicle, ramming other vehicles, you're going to have to do whatever it takes to stop them. For all the police officer knows, this guy in the van was trying to kill him.
That may be true in general, but this part seems odd: dispatchers were pleading with officers to “back off” in their pursuit. Sounds like whatever the cops did in this case was still a violation of some policy.