“Under the correct approach, a probable-cause hearing focusing on a dog’s alert should proceed much like any other, with the court allowing the parties to make their best case and evaluating the totality of the circumstances. If the State has produced proof from controlled settings that a dog performs reliably in detecting drugs, and the defendant has not contested that showing, the court should find probable cause.
But a defendant must have an opportunity to challenge such evidence of a dog’s reliability, whether by cross-examining the testifying officer or by introducing his own fact or expert witnesses. The defendant may contest training or testing standards as flawed or too lax, or raise an issue regarding the particular alert. The court should then consider all the evidence and apply the usual test for probable cause—whether all the facts surrounding the alert, viewed through the lens of common sense, would make a reasonably prudent person think that a search would reveal contraband or evidence of a crime.”
Does an alert now allow a search of any vehicle - vehicles going through a DUI checkpoint, for example - 'yes' or 'no'?