I believe that euthanasia should be practised as it has the persons best interests at heart. The patient should give their consent. However, if this is not possible the courts should decide on whether they have a poor enough quality of life to warrant such final actions. Relatives shouldn't decide as their judgement could be clouded/distorted due to the emotional stress of their relatives condition or influenced by inheritences.
~ The journey of a thousand miles begins with a single step ~
* Nothing in the world has ever been accomplished without passion *