> "hiring people to commit murder on your behalf is morally wrong."
No, unjustifiably murdering people is wrong. Killing someone for the "right" reasons, either by yourself or by proxy, is morally right.
> > Clearly the rightness of evading law enforcement and shooting blackmailers depends on the rightness of the law the enforcers are enforcing.
> That's not exactly clear, no.
Sure it is. You never taken a history class, or watched current events on TV, if you think all laws are equal and that all rulers have a right to be obeyed. Without recognizing a bad law you can't recognize good law.
> In fact it's less than clear, to me, that hiring a hitman is anywhere near the same moral level as "evading law enforcement."
Soldiers are hit men. Sending them some places results in war crimes, sending them other places prevents war crimes. Overall, I'd rather have and use soldiers than not.
For a meaningful comparison with "law enforcement", first specify which legal system and which laws.