The various roles we incorporate into the criminal justice system as well as the ways in which we construe such roles, lend themselves to the kind of ethical reflection that is open to us all. That said, once we have determined roles and their contours, those who act within them may have special duties and privileges that others may lack. Specific roles may generate ethical inquiries with novel forms, just as new technologies may push us in new directions.

Structurally I don't see a fundamental difference between what we may reasonably expect of police and doctors - though obviously the fact that doctors are generally pursuing life-saving activities and police may be engaged in life-threatening activities may lead to differences in how we construe the moral limits to their roles.

I grew up in a home in which loyalty to family was central to my father's outlook. Adolescent changes to my outlook (which set me against parental values) made me very critical of loyalty, reinforced by certain religious writers I found influential at that time. Harry Blamires, The Christian Mind. But I remained conflicted about loyalty.

Police have both extra constraints and extra permissions - on the one hand, they can't dodge involvement in social disorder as the rest of us can and they may be required to conduct themselves privately in a way that does not undermine their public authority; on the other hand, they have permission to engage in deceptions, invasions of privacy and uses of force that are forbidden to the rest of us. But this does not put them beyond common morality.

In later years, when I started working in police ethics, I was professionally drawn back to the topic but as well was better able to see two sides to loyalty - its importance for certain central human relations such as friendships, but also its corruptibility in the sense that loyalty could be invoked against other moral constraints: it sometimes function as something of a moral Trojan horse, undermining other moral considerations.

There will always be situations in which conflicts arise between individual and communal values - Catholic police officers deployed to enable women to enter abortion clinics without harassment and doctors who oppose performing abortions. No social role is free of such potential conflicts.

My mother thought my inclinations would do well in Law, but I was too shy and deliberative - slowfooted - for that, so I determined to be an English and German high school teacher. In my first year of university I had one subject to "fill in" and chose philosophy against the advice of my counselor. My university teachers in English and German were totally uninspiring; philosophy was wonderful and my results showed it. I chose it and basically backed into a situation in which only a philosophy career seemed a viable option. I've never regretted it, but there was a lot of serendipity.