I agree totally with what you said GeordieGirl. I think with this chap, he probably had some sort of personality disorder as well. This is hard to diagnose and not possible to treat.
We will probably not know the full truth, but I hope it does not increase the isolation of people with depression. It would be very wrong think that all people with depression/anxiety are dangerous.
When I was interviewed for my last job I did not tell them I had recently had depression and luckily they did not ask. There is always the fear you will be turned down because of it. However, for jobs where peoples lives and safety are at risk the situation should be different and some way should be found that is fair to the employee and safe for those his/her employment effects.