Life Choice ep.

At the end when Ben and Paul are debating on the law changing and what defines a criminal, it really makes you wonder how people who work in law deal with the fact that it's constantly changing. What sense does it make when today something is perfectly legal and tomorrow it's a crime? First Paul says a criminal is somebody who commits a criminal act, no matter what the reason, then says if the law hadn't changed, he'd be a slave...okay, but what if the law DIDN'T change? Or what about Prohibition? One day booze is legal, the next day it's illegal, and then a decade later it's legal again...exactly what's the point in claiming you fight for justice when the definition of it is always flip-flopping from one side to another?