Probably because they hope to get a plea bargain, even though a lot of them would drive away free if they demanded a search warrant
AFAIK in most places they don’t have to get permission to let the dog sniff your car.
It’s a legal technicality, but the dog doesn’t sniff the car, it sniffs the air around the car, at least until it alerts on something which may generate probable cause for a search of the car.
Re: No warrant for dog sniff
For private cars? I am very surprised to hear that.
They can sniff your luggage at the airport, but only after you voluntarily pass it over to the airline.
They can sniff for explosives almost anywhere.
But sniff a privately owned car for drugs with no warrant or permission - I am very surprised to hear that.
Only if there is no delay.
Rodriguez v. United States:
Unless police have “reasonable suspicion” of a crime, it is an unconstitutional seizure for them to extend a legal traffic stop in order to conduct a dog sniff.
Cops need probable cause to stop your car for a traffic violation. Then, they need more probable cause to search your vehicle, which includes the use of sniffer dogs.
If they do not have probable cause to search your car, any evidence found by the sniffer dog will be thrown out.
Here’s the scam...
They pull you over. They walk the dog around your car. The dog alerts. They ask your permission to search the car.
Job One for the driver...
Stay calm. Request a search warrant.
The cops know they can’t get a search warrant.
So, they badger you or goad you and try to get you to say or do something suspicious.
Stay calm, and keep asking for a search warrant, which will never come.