I've been thinking lately about how I react when somebody invokes the US constitution in a discussion. I cringe. I immediately want to leave that discussion. Why? Because, after hundreds of discussions - perhaps thousands since I've been active online for a long time - I have never seen mention of the constitution improve or advance a political discussion. Again, why?
The problem is not with the constitution itself. I certainly have a lot of opinions about what it got right, what it got wrong, what it left out, where the wording was sloppy, how any of it applies today, etc. I wouldn't mind discussing those in the proper context. After all, the constitution is part of an Enlightenment philosophical, political, and legal tradition that has only become richer in the more than two hundred years since. There's absolutely nothing wrong with making the arguments that the authors of the constitution once made, or might have made, so long as it's done in a way that recognizes their context and especially counterarguments that already exist. Such debates can be quite exhilarating and still amicable.
The problem is that, in debates on other subjects, the constitution is only ever invoked as way to stifle debate. It's always an appeal to authority and/or tradition, which are only relevant in a courtroom. Anywhere else, they're fallacies. Their use signals an abandonment of reason in favor of mere verbal bullying. The original Godwin's Law was an observation that comparisons to Hitler might occasionally be apt but could never be helpful. The same is true for "but my constitutional rights" kinds of arguments outside of courtrooms. Automatic disqualification, you lose, try bringing an original thought next time.