BISMARCK, N.D. (AP) — The North Dakota Supreme Court has denied an appeal by the parents of a North Dakota college student found dead after becoming an informant to drug investigators. Justices in an opinion released Tuesday upheld Judge Jay Schmitz’s dismissal last year of the wrongful death lawsuit. The Sadeks sued the Richland County Sheriff’s Department, one of its deputies and the county, alleging their son, Andrew Sadek, was killed because he was coerced into becoming a drug informant. The judge ruled there was no evidence that the sheriff’s deputy directly caused Sadek’s death or that the county acted negligently .