The New Mexico Supreme Court case of State v. Guthrie addresses the rights of defendants in probation violation hearings to due process and confrontation of the State's witnesses.
The court determined that the rights of probationers in probation violation hearings were measured on a "sliding scale with extremes at either end and much balancing and weighing of competing interests in between."
The facts of the Guthrie case are pretty straightforward. The defendant failed to complete a residential treatment program required under the terms of his probation. The probation officer that filed the probation violation report had been relocated and was unable to attend the hearing.