Prima impressionis

"First Impression" can also refer to a video game named Neon Genesis Evangelion: First Impression. A case of first impression is a case or controversy over an interpretation of law never before reported or decided by that court. There is no binding authority in a case of first impression.A case of first impression may be a case of first impression in only a particular jurisdiction. In that situation, courts will look to holdings of other jurisdictions for persuasive authority.Where no persuasive authority exists, a judge will look to legal analogies, legal commentary, legal briefs of the parties, and his or her own legal logic.
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On first impression