Well, the Supremes have historically mentioned English law and customs in cases. But our law came from English law. American common law is just a subset of English common law, so the justices trace back the meaning of common law at issue in some cases to the event in England that gave rise to it. Never used French, Italian, German or Chinese law before, though.
"Never used French, Italian, German or Chinese law before, though."
What? You don't consider our friends down in Louisiana to be Americans? New Mexico? Hawaii? Northern Maine?