Miles was slowly realising that they were back her to question him further because Lettie couldn't prove he was in Paris. Which meant he was a suspect in Rosmerta's death. "We were in Paris," he repeated again.
"I don't know why you suspect me of killing Rosmerta." He was still very confused. "I've told you what you need to know, and besides, Rosmerta was one of my son's baby sitters. Do you honestly think I'd kill someone he cares about? Especially when I have to sit and deal with the fallout of that?" His voice was raised just a touch, as he tried to get this Susan to see sense.
But then the surly one started thumping out accusations, throwing them one by one in his face. When he flat out made up some ridiculous story about how he was fleeing the country, he was about to laugh.
But then the man's finger was pointed in his face and his anger flared. His wand was out and he'd cast a stunner at the man before he'd realised what he was doing.