Continuity mistake: At the start of this episode Rossi tells Garcia about the case he's obsessed with, "It's the 20th anniversary of this crime. Twenty years tomorrow, three children woke up and found their parents murdered." However, during S3xE11 "Birthright," while working on their current Wilkinson case, Rossi shows Caulfield (the sheriff of the original Wilkinson case from 1980) the victim's charm bracelet he carries, then tells him about the Indianapolis case he's never forgotten, and how every year since then he's called the victims' children. And later, after Caulfield tells Rossi it's been 27 years since his own unsolved case, he asks Rossi how long it's been for him and Rossi says, "21," then Caulfield cautions, "Don't let it get to 22."
Continuity mistake: When Rossi is telling Prentiss, Morgan, and JJ about the original Galen case, he says that the Galen parents were butchered with an axe, but in "Birthright", he tells Detective Caulfield that they were beaten to death.
Chosen answer: Black SUVs are common police, military and dignitary vehicles around the world. It is not too much to assume they could be rented or owned by the police forces in the areas.
kristenlouise3
Other people have explained it but fore more information, federal cars would most likely be brought to the airport from the nearest agency, so they can drive out to their locations especially in rural situations.