Often the bride's mother is the recognized arbiter of appropriate attire and behavior at a wedding, if she's qualified and willing. I understand that this is a reception, not the wedding, but I think it would be gracious to consult her unless you have persuasive evidence of her lacking judgement. Your parents, because of their familiarity with Scots' attire, your circumstances, and the personalities of the bride's mother and some of the other guests, probably can offer good advice.

I think the key to fitting in at most social affairs is doing what is expected. The real challenge is in figuring out in advance what will be expected, and for that knowing the players is often more helpful than knowing the rules.

Best wishes for a very good time at the reception.

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