MARINETTE, Wis. (AP) — A competency exam has been ordered for a man accused of killing a couple in a Marinette County park in 1976.

Raymand Vannieuwenhoven, 82, is charged with two counts of first-degree murder in the deaths of 25-year-old David Schuldes and 24-year-old Ellen Matheys at McClintock Park in Silver Cliff.

The exam, approved by a Marinette County judge this week, will determine if Vannieuwenhoven understands the court proceedings and can assist in his defense. The results will be discussed at a hearing Feb. 21, WLUK-TV reported.

Vannieuwenhoven pleaded not guilty last year.

For decades, the widower and father of five grown children lived quietly in Lakewood.

Investigators didn’t have any major leads until 2018, when a DNA lab in Virginia identified the genealogical background of the suspect. Investigators say tests of Vannieuwenhoven’s DNA from a licked envelope matched DNA collected at the crime scene.