I believe that it's the only moral thing to do.
In schools we learn that obeying is good, disobeying is wrong.
Well look at history, all those order followers that drop bombs, torture people, millions died in gulags and concentration camps. It would have been better if all those would have followed their own conscience instead of "just doing their job just following orders".
And that's his free will, to disobey his leader. But as for their Law; disobeying your leader is a violation and has a consiquence.
You can quit or not join in the first place.
I have no ruler, or leader as you call it, who's opinion stands above my moral compass/conscience.
This video explains well what Law is.
But before you enter the course of being a cop, there's a lot of briefs and you can search what you will, do what to do and what are the rules that you need to consider.
I think that SWAT knows what is right and moral for him.
Truth