Establishing price fixing and all other Sherman Act Section 1 violations requires proof that a contract, combination, or conspiracy produced the alleged wrong. Evidence of collusion arises in a variety of ways. Optimally but uncommonly, the plaintiff can produce explicit evidence (such as a written document) of a direct agreement among the defendant parties. 

Question 

To replace call arounds, could La Quinta lawfully check competitors’ prices on the Internet, make “blind” calls to competitors, or employ “mystery” shoppers?