When the team go the Jocelyn house to arrest her they find a body in the bedroom who has been shot in the head, the first shot shows blood near the victims head and is pinkish in color, the close up shows darker colored blood appearing partly under the victims head.
The poison is identified as foxglove (digitalis). But this would not cause bleeding from orifices (in contrary to the correctly mentioned rat poisons), it would cause heart failure.