In an action for malicious prosecution, probable cause does not depend upon the actual state of the case, in point of fact, but upon the honest and reasonable belief of the party prosecuting. 2 Greenl. on Ev. 13th ed. § 455. If the prosecutor has an honest, though, mistaken, belief in the truth of the charge laid in a criminal complaint, it is evidence of probable cause.King v. Colvin, 11 R.I. 582.
In the present case, we think it is apparent from the testimony that the defendant honestly believed that the plaintiff had changed the center stone in the pin left with him to be repaired; that his conduct was consistent with such belief and that from his point of view it was upon reasonable grounds, because he had not known of any change in the stone before that time. The jury must have found that he was mistaken in stating that there had been no previous change; but it does not follow that he could not reasonably have believed this to be the fact, although he claimed to be an expert in diamonds, since the plaintiff himself, also an expert, testified that he did not and could not detect the spuriousness of the stone under an artificial light with a magnifying glass.
The defendant stated the facts in full, as testified to by him in the trial of the complaint, to an attorney at law of *Page 292 this State, and was advised that he had a good cause for prosecution. There being no substantial denial of these facts, which are sufficient to constitute a defence to an action for malicious prosecution, the court is of the opinion that the verdict is against the evidence in this respect.
New trial granted.