Laws surrounding murder by and large aren't all that important. If it wasn't illegal you'd just have mob justice filling the gap, as murder is generally frowned upon quite severely by society.

Ideas surrounding freedom, liberty, and privacy are very complex, easily confused, and often forgotten until its too late. The laws around these things are mechanisms which help protect what you're country supposedly holds dare.

But in answer to your actual question, would you believe them if they said they hadn't?

I was referring to https://en.wikipedia.org/wiki/Supremacy_Clause