If someone was threatening me in any way I would not hesitate in getting a restraining order.
If someone threatened a family member, I would act even quicker -or bypass 'the law' entirely.
Things get a bit tricker when dealing with financial matters such as someone cheating you or taking something then not paying. I would judge everyone of these situations as a case-by-case, but going to the law or courts would be the LAST thing I would do after other options were explored.