John G. Roberts Jr.
Role at the time: Chief justice, writing the Court's majority opinion
Defended or excused
Response to this claim
An objectively reasonable mistake of substantive law can justify a traffic stop under the Fourth Amendment.
“The Fourth Amendment tolerates only reasonable mistakes, and those mistakes—whether of fact or of law—must be objectively reasonable.”
Read the original text (opens in a new tab)Heien v. North Carolina: majority, concurrence and dissent · Supreme Court of the United States574 U.S. 54, Roberts pages 57-68; Kagan pages 68-71; Sotomayor pages 71-80
The full opinions set out the disagreement over whether an objectively reasonable mistake of substantive law can justify a traffic stop.
Archived copy (opens in a new tab)Why we used this label
He supports allowing the stop on this basis, the conduct and rule at issue.