The High Court's "thinly veiled" hope the DPP would adopt a "humane" approach to the case of terminally ill Marie Fleming does not alter the fact that the court upheld the criminality of the offence of assisted suicide, the Attorney General has told the Supreme Court.

Answering questions from the court, Shane Murphy SC, for the AG and State, said the three-judge High Court ruled the absolute ban on assisted suicide was a justified and proportionate measure and it remains "a free-standing criminal offence".

The DPP retains the discretion whether or not to prosecute any such offence but had also told the High Court she could not issue offence-specific guidelines indicating in what circumstances any such prosecution might be taken, he said.

The absolute ban on assisted suicide was intended to protect against a risk to life and lifting it would create an enormous risk to others, he said.

The intention behind the ban was to prevent people interfering with the right to life of others and to deter conduct considered by the State as against the interest of the public good. There was "a compelling public interest" in retaining the ban.

The European Court of Human Rights had in another case ruled such a blanket ban was a proportionate measure, he added.

There are many wishes people have that the law may legitimately control or prevent being exercised in the public good, he argued.

While he accepted the ban restricted Marie Fleming's autonomy rights, there was a "good reason" for that and she could still exercise autonomy in other respects.

He was making submissions in the continuing appeal by Ms Fleming against the High Court's rejection of her challenge to the absolute ban on assisted suicide in Section 2.2 of the Criminal Law Suicide Act 1993.

The appeal is expected to conclude later today after which the seven-judge court, presided over by the Chief Justice, Ms Justice Susan Denham, is expected to reserve its judgment to a later date.

Ms Fleming (59), living in Co Wicklow, is in the final stages of Multiple Sclerosis and wants orders which would allow her be lawfully assisted in fulfilling her wish of taking her own life at a time of her choice.

In her particular circumstances as a severely disabled person unable to take her own life unaided, the ban disproportionately infringes her personal autonomy rights under the Constitution and European Convention on Human Rights, she claims.

She also claims the ban is discriminatory in that an able-bodied person may take their own life lawfully but she cannot be lawfully helped to do the same.