Would you lie to prevent accurate enforcement of an unjustified law?

Here's something I'm thinking about vis-a-vis my article and I thought it might be fun to hear people's thoughts.

If you knew and saw A did X in front of you, where X is a crime that you think is unjustifiably criminalized because at bottom you think X lacked any morally blameworthy feature (e.g., pot possession/handgun possession/eating on the subway, whatever), how many of you would lie if the cop asked you (Did you see A do X a moment ago) or if the court called you as a witness--in order to prevent accurate enforcement of the law against A?

I take it some of you might be willing to lie or not answer if A if A was family/friend--true? But perhaps that would be the case even if X was a justified crime in your mind? In any event, how many of you think you should lie, but doubt you would because you fear the perjury/false statements criminal liability to you if you did? What are some of the other options you think are desirable as a moral agent facing this quandary?

I'd be curious to see what your intuitions are when you tweak the scenario in several ways too:

a) imagine you think X should be permitted conduct but you think the law banning X is nonetheless morally legitimate even if you don't think it's  all-things-considered justified in your view to have a criminal law prohibiting X.  (This is kind of like saying you think the law passes muster under a deferential reasonableness review). Would you lie then?

b)  imagine you think X is impermissibly criminalized because the law is so spectacularly dumb that it couldn't survive deferential reasonableness review (e.g., a prohibition on chess). Would you lie then?

c) imagine you think the law banning X is illiberal (ie. and e.g, it violates a core political right such as free speech) (perhaps X is flag burning). Would you lie then?