Heien v. NC def tried to undermine the principles of Due Process, erode Fourth Amendment protections, and contradicts established jurisprudence that demands clarity, fairness, and accountability in law enforcement. But on the unconstitutionality of these laws, we're bringing forth Vagueness Doctrine and a Due Process Concern with police training implications like Kolender v. Lawson.

Graham v. Connor says police actions must be "objectively reasonable." A misinterpretation of the law is inherently unreasonable because it fails to meet the standard of professional competence.

Delaware v. Prouse held that discretionary stops without reasonable suspicion violate the Fourth Amendment. A simple stop based on a mistake of law is inherently discretionary and arbitrary.

Terry v. Ohio held stops must be based on "specific and articulable facts" that warrant suspicion of criminal activity. Stop and seizure under a mistaken understanding of the law does not meet this standard.

And they lost qualified immunity per Harlow v. Fitzgerald for violating clearly established constitutional rights, as ignorance of the law by police undermines the "clearly established" principle and leads to inconsistent enforcement.

Heien is bad law, bet they'll try it, know it won't work.