I'd think you are also more likely to be a serial killer if you simply have the opportunity. Nurses, doctors, carers all have access both to 'easy' victims and the knowledge of how to disguise their crimes. As well as having the presumption of virtue in their favour. If you manage a Sainsbury's and the cashiers start going missing you'd probably be a suspect fairly early on.
True, but using that example, it would be more like Sainsbury trying to prove that a cashier was poisoning customers by adding salmonella to the rotisserie. Which is harder to prove.
I'd think you are also more likely to be a serial killer if you simply have the opportunity. Nurses, doctors, carers all have access both to 'easy' victims and the knowledge of how to disguise their crimes. As well as having the presumption of virtue in their favour. If you manage a Sainsbury's and the cashiers start going missing you'd probably be a suspect fairly early on.