A small breach of protocol briefly intruded into the otherwise immaculate scene.
Times, Sunday Times
A royal insider called it a breach of protocol.
The Sun
With anyone else, it might have been a serious breach of protocol.
Times, Sunday Times
It would be a breach of protocol if we didn't let them freeload at our expense.
Times, Sunday Times
She either didn't hear or tactfully ignored this disgusting breach of protocol.
Times, Sunday Times