Actually when they violate the law and someone dies as a result of their actions it is criminal.
No, "criminal" is when a person violates a penal statute. You need to learn the difference.
Violating federal law is not part of their official responsibilities and they are culpable.
Where is the violation of federal law? Can you identify the statute? Of course you can't. The city has no obligation to partake in federal immigration enforcement. The mayor has no obligation to establish public policy that will aid, compliment, or endorse federal immigration enforcement.
Fake ass CINOs like you constantly claim to be supporters of state's rights and local governance, but you're really just fair-weather bullshitters. You talk a big game about state sovereignty and nullification when it comes to gay marriage and Obamacare. But when a city or state does something you don't like, you're suddenly up in arms about how they were
supposed to do what you wanted them to, because OMGFEDERALLAW!
Sanctuary cities are a state and local issue. Such policies are the 100% the right of the cities and states in question, each having no obligation to enforce federal immigration policy. Personally, I think sanctuary cities are bullshit. But it is ultimately an issue for the people of that city to decide. True conservatives will support the right of local and state governments to lawfully rebuff federal immigration policies, even while hating that state/city's position on immigration policy.