The "Constitution-Free Zone" (coined by the American Civil Liberties Union) where border agents can question and detain anybody:
Background from a Government Accountability Office Report:
When establishing checkpoints, the Border Patrol must take into account court decisions ruling on the parameters of immigration officers’ authorityto conduct inquiries concerning illegal aliens. The legal authority of immigration officials to establish permanent checkpoints and stop vehicles transiting through them has been confirmed by the Supreme Court in United States v. Martinez-Fuerte.14 The Supreme Court ruled that government officials may stop vehicles at permanent interior checkpoints for brief questioning of the driver and passengers without reasonable suspicion. The Court held that it was constitutional for the Border Patrol, after routinely stopping or slowing automobiles at a permanent checkpoint, to refer motorists selectively to a secondary inspection area for questions about citizenship and immigration status on the basis of criteria that would not sustain a roving patrol stop.15 (15A roving patrol stop is a stop by an agent who patrols in a vehicle but who is not assigned to a particular location.)
The Court determined that the constitutional interests of motorists at these checkpoints were not violated, for a number of reasons. It found that the checkpoints, with flashing lights and warning signs, provided advance notice to motorists of an official roadblock that was applicable to all motorists.16 Motorists were not taken by surprise, as they knew, or could find out, the location of the checkpoints. Furthermore, the Court concluded that the regular manner in which established checkpoints were operated was visible evidence that the stops were duly authorized.17 (14428 U.S. 543 (1976).)
From the extremely independent minded but legally uneducated individual who went out of his way to challenge this legal authority, stop highway traffic, and waste taxpayer money (video below) I really can't see how in his specific cases his rights were being infringed upon. If he would have stopped, showed ID, answered a question or two and moved on he could have saved a half hour of his life and not gotten so upset over what amounted to a minor inconvenience.
I can see why there is concern about civil liberties and effective use of taxpayer dollars in borderline cases where Border Patrol questions people at bus and train station about their immigration status. This has been criticized by immigrant and civil liberties advocates who These kind of accusations racial profiling and assaults on civil liberties should be taken seriously, but I don't agree with the actions of the individial below who, in his specific situation overreacted horrifically to what amounted to a short traffic stop which didn't significantly infringe upon his rights.