From Gorman v. Stites & Harbison, NPO, COA, 4/29/2011

The question of probable cause underlying the tort of wrongful use of civil proceedings does not turn on whether a court subsequently decides the attorney erred in his view of the law, any more than it turns on whether he was subsequently unable to prove his client’s claims regarding the facts, so long as his views were tenable at the outset.

What facts and circumstances amount to probable cause is a question of law. Whether they exist or not, in any particular case where the evidence is conflicting, is a question of fact, to be determined by the jury. But where there is no conflict in the evidence, whether the facts shown amount to probable cause, is ordinarily a question of law for the court.
Craycroft v. Pippin, 245 S.W.3d 804, 806 (Ky. App. 2008) (citing F.S. Marshall Co. v. Brashear, 238 Ky. 157, 37 S.W.2d 15, 17 (Ky. 1931)).