On the highway entrance checking for drunk driving, the traffic police officer stopped my partner.

He tested once, the result was zero, but he still didn't retract the detector.
He said, "Why is your face so red?"
My partner said, "I'm from the south, I get flushed when nervous."
The traffic police said, "Blow again." He blew, still zero.
He said, "I'm really nervous, look, my partner is sitting in the front passenger seat, and he hasn't dared to say a word since earlier."
I really didn't dare to speak because I was sitting in the front passenger seat, holding two jin of spicy soy sauce biscuits I just bought from the roadside, still warm.
He pressed the detector against the biscuit bag and said, "These biscuits were just bought. We've been driving out of the city for half an hour, and the biscuits are still hot, indicating the car isn't going fast. The heat that hasn't dissipated is more accurate than alcohol."
The traffic police looked down at the biscuits and asked, "What were you two talking about just now?"
He said, "We've been arguing about whether to take a detour home. We've argued for forty minutes and still haven't reached home. The fuel cost is already more than hiring a driver."
The traffic police smiled and retracted the detector.