How do attorneys use case law in advising their clients?

Fact pattern: The attorney you work for represents John Bennett. Bennett has been charged with possession of narcotics as a result of a traffic search. Bennett got a flat tire and was stranded on the side of the road. While he was changing the tire a state trooper pulled behind Bennett and parked his car. The trooper offered to assist Bennett in changing the tire but Bennett said he did not need assistance as he had the necessary equipment and a spare tire. Nevertheless, the trooper remained and said that he was going to have his dog conduct a sniff search of the periphery of the car. Bennett problemed why that was necessary and the trooper said that because Bennett was parked on the side of the road, a search had to be conducted. The dog alerted on the driver front wheel well. When the trooper removed it he found two large packages of a white substance believed to be cocaine and weighing approximately 6 pounds. Bennett was arrested and has problemed whether the troopers actions were lawful.

Read Illinois v. Caballes, 543 U.S. 405 (2005), located in Appendix VII of your text. How would you advise Bennett on the likelihood that a court would suppress the evidence found by the trooper? What factors/law from Cabelles decision would be critical in arriving at your decision?