I understand the basic premise, but I wish your examples were more pertinent to the situation we are discussing so I could better see how this relates.
There are two parts here.
First is the tautological nature of your first sentence; if it is banned, then by definition the creation of such makes one a "criminal", where it would seem that you infer a class of person in the first sentence.
Given a potential misreading of the first portion, the second is clearer:
> and criminals by their nature don't have the moral qualms with committing further crimes.
Again, you assign "nature" to a "class" by definition. It may be legal to murder / sentence to death someone over gender, race, selling alcohol or marijuana, or otherwise. Even sitting in a bus in the wrong spot could result in being labeled a criminal.
I am reasonably certain you didn't intend to paint the above examples of criminality as somehow correlating to a lack of morality. "Further crimes" is a slippery slope trope, where no such predicate exists without examining the contexts of the initial crime. Again, think about sitting on a bus in the wrong spot. “Serial offenders” here might be celebrated later.
Hence the caution against using the term. There are a good number of laws currently that, after some duration of time, may seem anywhere from dated to outright bigoted / horrible. "Criminality" is a social construct, and as such, we should be skeptical and careful about the erroneous connective tissue between criminality and some sort of Humanist trait attachment.