I myself are not convinced with modern day man made laws but prefer to take thing happens at its own course, i.e. let nature takes its own course.
Just look at a hypothetical example, which is happening in real life. A man who murder another man, when caught, face the modern day man made laws, goes on trial, and is not sentenced to death as the trial judge found the evidence produced to him are not beyond reasonable doubt. The murderer escaped death sentence, walk out as a free man. What’s next? Will this means the murderer really free from his own conscience?
If there is such a thing of going on trial of the murderer in religion point of view, I believe there is no such sentence as ‘hang until dead’ for a murder but let nature takes its own course. That summed up my understanding of “Law of Kamma” founded by my great teacher, Buddha.
Repent and do more good deeds is the way to go for a murderer, if he is fortunate not to be caught, or convicted under modern day man made laws.
Having said the above, we still need to observe our own actions and not to disregard man made laws, if we choose not to be unfairly convicted.
Easiest way is to observe the 5 precepts of Buddha’s teachings, and let nature takes its own course from there.