Norm has an argument by Eve Garrard in favour of legalising voluntary euthanasia, with strict controls. Go and read it, but in brief the argument is this: voluntary euthanasia is justified in at least some cases; legalisation might lead to undue pressure being placed on other people for whom voluntary euthanasia is not justified, and who would not otherwise seek to end their lives; resisting legalisation for the sake of this group involves sacrificing the legitimate claims of those in the first group; such a sacrifice should not be made, and the problem posed by the second group should be dealt with by strong regulation rather than by an outright ban on voluntary euthanasia.
The most obvious problem with this argument is that it takes as axiomatic something which is in fact strongly contested, namely that "There are good reasons for permitting some cases of voluntary euthanasia, grounded in the desire to prevent terrible suffering, and respect for autonomous choice". But for many people (not for me, admittedly, but that's for another time), that does indeed go without saying, and so I'm more interested in looking at the way the argument works later.
Garrard says that an outright ban on euthanasia for the sake of the group of people who may otherwise be unduly influenced to end their own lives involves "sacrificing" those whose suffering can't be relieved, and who do really want to end their own lives. She says that sacrificing some for the sake of others in this way is not something we normally permit in healthcare.
There's an illicit argumentative move here, I think, and it's in Garrard's use of the word "sacrifice". When we talk of someone being "sacrificed", we normally mean that they are being killed for the sake of some sort of greater good. But other things can be sacrificed - given up for the sake of a greater good - too: aspirations, desires, cigarettes, all sorts of things. Most would agree that even if the word "sacrifice" is appropriate in both cases, sacrificing a person isn't the same, or as serious, as sacrificing a desire. Banning euthanasia may involve sacrificing the legitimate desires of a particular group of patients, but it doesn't involve sacrificing those patients themselves; on the contrary, it involves keeping them alive. The confusion between different uses of the word "sacrifice" is what allows Garrard to say that in healthcare we don't normally permit the sacrificing of some for the sake of others, and to imply that banning euthanasia is inconsistent.
In any case, of course, sacrificing some for the sake of others is something we permit in healthcare. Decisions about which patients to treat first when resources are scarce, and about which life-saving but expensive drugs to allow the NHS to prescribe, are made all the time. In those cases, the decisions which are made may well result in the foreseeable deaths of patients. A decision to legalise euthanasia would certainly result in the foreseeable deaths of patients. Keeping euthanasia illegal would foreseeably result in patients suffering, but not in their being sacrificed.