It’s not entirely true that ‘law’ would be a mass noun in that context. Are all the laws only used for a specific purpose? Isn’t life unrealistic? Where ‘laws’ mean laws, some of them may be, but not necessarily all of them, are to serve a specific purpose. The sentence definitely needs ‘are’, not ‘is’, because the ‘and’ in ‘law(s) and enforcement’ create a plural subject of the verb.

In other words, the word for “don’t do anything” is not an example.

Everytime I change a character, the comma should be deleted.. What follows is the very basic idea of meaning of a sentence?

And ‘that’ may be omitted.