The best distinction I've seen between the two consists in whether you honour or promote your values.
Say I value not-murdering.
If I'm a consequentialist, I'll act on this by trying to maximise the amount of non-murdering (or minimising the amount of murdering). This might include murdering someone who I knew was a particularly prolific murderer.
If I'm a deontologist, I'll act on this value by honouring it: I'll withhold from murdering anyone, even if this might increase the total amount of murdering.
Unfortunately I can't remember offhand who came up with this analysis.
Good point. This also explains why we are so willing to delegate "killing" to external entities, such as job occupations (when the "killing" involves chickens and cattle) and authorities (when we target war enemies, terrorists and the like. Of course this comes with very strict safeguards and due processes.) More recently, we have also started delegating our "killing" to machines such as drones; admittedly, this ignores the truism that drones don't kill people, people kill people.
Maybe if we were less deontological and more consequentialist in our outlook, there would be less of this kind of delegation.
I think there’s a confusion in our discussions of deontology and consequentialism. I’m writing this post to try to clear up that confusion. First let me say that this post is not about any territorial facts. The issue here is how we use the philosophical terms of art ‘consequentialism’ and ‘deontology’.
The confusion is often stated thusly: “deontological theories are full of injunctions like ‘do not kill’, but they generally provide no (or no interesting) explanations for these injunctions.” There is of course an equivalently confused, though much less common, complaint about consequentialism.
This is confused because the term ‘deontology’ in philosophical jargon picks out a normative ethical theory, while the question ‘how do we know that it is wrong to kill?’ is not a normative but a meta-ethical question. Similarly, consequentialism contains in itself no explanation for why pleasure or utility are morally good, or why consequences should matter to morality at all. Nor does consequentialism/deontology make any claims about how we know moral facts (if there are any). That is also a meta-ethical question.
Some consequentialists and deontologists are also moral realists. Some are not. Some believe in divine commands, some are hedonists. Consequentialists and deontologists in practice always also subscribe to some meta-ethical theory which purports to explain the value of consequences or the source of injunctions. But consequentialism and deontology as such do not. In order to avoid strawmaning either the consequentialist or the deontologist, it’s important to either discuss the comprehensive views of particular ethicists, or to carefully leave aside meta-ethical issues.
This Stanford Encyclopedia of Philosophy article provides a helpful overview of the issues in the consequentialist-deontologist debate, and is careful to distinguish between ethical and meta-ethical concerns.
SEP article on Deontology