The public prosecution department is asking the Supreme Court for clarity in the case of the euthanasia of an elderly woman with severe dementia.

Earlier this month, a lower court found the doctor who carried out the euthanasia not guilty of murder and cleared her of all charges.

A public prosecution department spokesman said on Thurday the case is being taken to the Supreme Court, not to dispute the verdict but to clarify the law.

In particular, officials want clarity about how doctors should deal with patients who are not in a position to confirm their wish to die. The case centres on a 74-year-old woman who had drawn up a living will some years before her admission to the nursing home and had regularly stated that she wanted to die.

Judges in The Hague ruled that the euthanasia was carried out with proper care and that doctor, who has since retired, did not have to verify her patient’s wish to die with the patient because she was incapable of responding.

In addition, the court said it supported the doctor’s decision to put a sedative in the woman’s coffee to calm her before euthanasia drugs could be administered because it had made her as comfortable as possible. The sedation took place in the full knowledge of her family.

Euthanasia is legal in the Netherlands under strict conditions. For example, the patient must be suffering unbearable pain and the doctor must be convinced the patient is making an informed choice. The opinion of a second doctor is also required.

Since the legislation was introduced in 2002, there have been a number of controversial cases, including a woman suffering severe tinnitus and a serious alcoholic.