The accused, then 18, signed a statutory declaration purporting to be a "parent or guardian" so her friend, aged 16, could secure a false ID from Service Tasmania.

The youth was issued a personal ID card, under a different name, and was later caught using it in a licensed venue.

Justice Ewan Crawford said it was clear the accused could not have been a parent or guardian of the youth.

"That's the bit I don't understand, how can she be a parent or guardian when you look at them side by side," he said in the Launceston Supreme Court yesterday.

"The officer at Service Tasmania shouldn't have done it."

Defence counsel Alan Hensley agreed saying the declaration should have been "rejected on the spot".

Mr Hensley said his client never intended to take part in the rouse but was asked to sign the document once inside Service Tasmania.

He said the identity card was "solely for the purposes of drinking and gambling" not a sophisticated attempt at financial gain through identity theft.

The accused was ordered to pay $50 to the victims of crime compensation fund and placed on a two-year bond but escaped conviction.