A couple will walk free, innocent after being the prime murder suspects in the disappearance of a young intellectually disabled mother in rural NSW over two decades ago.

The man and woman, who cannot be legally named, lived on a property in NSW’s south-west slops adjacent to where the teenager lived on and off with her extended family.

In late 2000, the girl moved onto the couple’s property and formed a sexual relationship with the then 40-year-old man, becoming pregnant and having a child.

The 19-year-old was last seen at her flat in a nearby town on June 2, 2002. A police investigation was launched into her disappearance.

On Monday in front of a packed courtroom, Justice Julia Lonergan acquitted the couple of the girl’s murder after a 28-day judge-alone trial in the Supreme Court.

Medical experts and family evidence given to the court showed the young woman as someone with the mental capacity of a 12- or 13-year-old who could be easily led by others.

The pregnancy came after the man’s wife had three miscarriages and one still-birth after her first child was born.

The couple always denied having anything to do with the girl’s disappearance.

1800 RESPECT 1800 737 732

National Sexual Abuse and Redress Support Service 1800 211 028

-AAP