When it comes the rules of evidence, there can be a big difference between a "policy" and a "habit" (or "custom," when it comes to a business entity). A decent (albeit nonlegal) illustration of the difference is the late Howie Sugden.* Howie had a policy of fighting anyone during pickup hockey games who, in his opinion, "played cheap." So while there was a decent chance his gloves might come off whenever he took the ice, it wasn't necessarily guaranteed. But when it came...
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