Have you ever poisoned someone? Been poisoned? Been paranoid of having been poisoned? Threatened or were threatened with poisoning? Heard or known of others who poisoned, were poisoned, threatened to poison, or were paranoid of having been poisoned?
If not poison, then how about ensuring other nasty things get into people's systems?
In all cases, what were the motives? Revenge? To get someone outta the way? Fun? And what about methods - spike their drink while they weren't looking?
Edit: Oh yeah, guess I should ask if you noticed any peculiarities to the people involved in poisoning, e.g. were certain PDs prominent, and do you think they contributed to cause such an incident to come about?