Your question reminded me of the concept of "situation ethics," a term coined by--interestingly enough--an Episcopal priest by the name of Joseph Fletcher (1905-1991). See http://www83.homepage.villanova.edu/richard.jacobs/MPA%208300/theories/situationism.html.
"Sometimes called 'contextualism' or 'relational ethics,' situation ethics maintains that the collective wisdom of the past can be used to guide ethical decision making in the present but must be set aside if love requires something else" (ibid.).
As with many, if not most, ethical theories, there is an element of truth to Fletcher's theory of ethical behavior. How big an element depends on a number of things, not the least of which is the situation or scenario to which the theory is being applied!
Hypothetically, if a bad person--and a complete stranger to me--were to break into my home, threatening the life of my spouse, and I had a loaded gun at my disposal, would I be justified in shooting (even shooting to kill) the bad guy? Both the Law of God and the laws of Pennsylvania where I live, would hold me guiltless, particularly if the bad man threatened the use of deadly force (i.e., he himself brandished a lethal weapon, such as a gun, or knife, or baseball bat).
Even this seemingly clear-cut scenario may not be as clear-cut as it seems at first, especially if we "tweak" the scenario a little. What if, for example, I know or sense the intruder is mentally deranged, and he threatens my wife with an imaginary (i.e., invisible) ray gun he's supposedly holding in his hand, while demanding I give him want he wants. The laws of Pennsylvania would likely still exonerate me, but what about the Law of God? Here is the crux of the matter.
We all know that when "the authorities that be" order Christians to stop spreading the gospel, we must appeal to a higher authority (Acts 5:29). That appeal does not exempt us, however, from using sound judgment when we choose to "flout" the law, particularly if in doing so we endanger the lives of other people, Christians or non-Christians alike.
For example, in a repressive regime, the powers that be might forbid the printing of Bibles or any religious literature. I as a Christian have a computer and a printer and my friends and neighbors are unbelievers. Moreover, they are genuinely interested in the Christian faith. Do I then post a sign with foot-high letters on my front door that says "FREE CHRISTIAN LITERATURE AVAILABLE HERE, 24/7"? Of course not.
I'd probably hide my computer and printer under the floorboards inside a closet, and during the wee small hours of the morning would retrieve the printer and proceed to do covertly what I believe to be the will of God. Later I would look for opportunities to distribute the literature covertly. Why covertly?
First, not to do so would be stupid! Boldness in the face of imminent persecution is one thing; stupidity when there is no direct threat of persecution is quite another. How will my friends and neighbors hear about Christ if I am in prison or dead because I stupidly put a billboard on my front door?
This example may seem preposterous, but I hope it at least illustrates the importance of balancing the demands of God's law that we be in subjection to the authorities He has established, with some equally important concepts of love, justice, conscience, and discretionary wisdom. Is there a hierarchy of right and wrong? Of course. Personally, if the authorities come looking for my wife, whom I know has done nothing wrong, and they ask me menacingly, "Do you know where your wife is?", guess what I'm going to do? I'm going to lie to the very best of my ability!
On the other hand, Corrie ten Boom, author of The Hiding Place, tells the story of her sister (I believe) who had a particularly sensitive conscience. Consequently, when during World War II the German soldiers came to her house in Holland and asked her pointblank "Are you hiding Jews in this house?", not wanting to "lie" she said nervously but with a hint of facetiousness, "Why yes, sir, they are here under the table!" The fact was, the Jews were under the table but were hidden by a large tablecloth. Thankfully, the soldiers thought she was kidding and failed to look under the table. She likely let out a huge sigh of relief. Phew!
Was Corrie's sister being overly sensitive, if not foolish? That's not for me to decide. Would I have said anything different? Probably, but then God knows what is in our hearts, and when we act in faith by doing what we think God wants us to do, we can be confident that God has our back!
Similarly, in a war scenario, a Christian soldier may feel perfectly justified in shooting an enemy soldier who is shooting at him. On the other hand, if his commanding officer tells him to open fire on a group of unarmed, bound and gagged enemy soldiers, would he be justified in either obeying the order or in defying the order? It is at that very moment the soldier needs to consult his conscience, say a quick prayer (as did Nehemiah, for example, in Nehemiah 2:4), and make a decision.
Personally, I hope he would choose to disobey the order. Perhaps, however, the Lord might tell the soldier to reason with his commanding officer first, before deciding to obey or disobey. You, on the other hand, might feel differently. That's OK, too, although if you think the soldier is justified in pulling the trigger, I would love to debate you as to why I think you are wrong!
Nevertheless, God is ultimately the judge of us all. As Abraham asked so long ago, "Will not the Judge of all the earth do right?" The answer of course is yes (see Genesis 18:25).