Its better to have the police knock down the doors of doctors suspected of preforming such procedures and having them stripped of their license and brought up on manslaughter charges.
Actually, that might happen to doctors who don't follow the protocol.
It has happened with doctors not following the euthanasia-for-adults law. Some have been found guilty to murder, not even manslaughter. However, because they only deviated slightly from the law (they did have consent from a terminally ill cancer patient but they forgot to consult a second doctor for example) they weren't sent to prison. However, a nurse who killed patients without their consent (like the British Doctor Death) was sentenced to life in prison.