The Happy Face Killer An Anthology of True Crime

On January 23, 1990, a college student driving around in the outskirts of Portland, Oregon, noticed a body lying in an embankment off the highway. The young woman was half-naked, and investigators discovered that she had been strangled, the rope still looped tightly around her neck. The student was immediately considered a suspect, and an interview was done at the police station. He stated that he had just done his finals, and decided to take a drive to clear his head when he spotted the body.
His story sounded plausible, but since it had been raining at the time, investigators found it odd that he chose that time to take a scenic drive. To make sure all their bases were covered, they called the school and managed to confirm the student's story. This left them with no suspects, and the victim's identity was still unknown. They released various details to the media, hoping that someone would recognize the woman.
The plan panned out... The victim's identity was discovered but the question remained... Who killed her?