Jefferson expected exactly the reaction that the young woman showed. His nervous sight betrayed her words, so the officer could realize that the situation was going straight on the direction he wanted to head it.
-The coffee can tell many things about someone.- Takes a short sip, rounds his eyes and puts his can ahead of her, adding the next words on the mean time:
-You can be sure now that the coffee is clear. Why would we envenom you with a coffee when we got plenty of aromatic kind of teas. The venom changes the coffee's flavour. Smells different and of course tastes different.
He was trying to get closer to her and make her get confy, so he could get rid of that.