Note that the Constitution protects pre-existing unalienable rights; it doesn’t grant those rights.
The “color of law” section of Title 18 deals with both rights protected by the Constitution and by other statutes, such as civil rights legislation.
The statute exists specifically to sanction anyone acting with the power of a governmental or quasi-governmental office that results in the deprivation of protected rights. Because of the authority of their office, officials are able, in practice, to take actions against the populace when, in law, they have no valid legal basis for doing so. Note also that any law that violates the US Constitution is void, at least by Supreme Court precedent.
But there’s little advantage in attempting to explain this to a jackbooted thug in a uniform on the street. And the big question is: who is going to prosecute officials for overstepping their bounds? No one here can have much confidence in the DOJ.