The courts took generations to work out a new definition of arrest, and it's still not satisfying. It's something more than a stop, but that's about all they know.

There you go: Two or three generations of jurisprudence in one panel.

Never fear.  The courts are chaotic here because they’re focusing on outcomes without a consistent underlying principle.  But I think I can give you one that makes everything clear.  Maybe next time I’ll explain it for you.  Watch this space!