The Salt Lake Tribune reported on July 17 and 24 about the hit-and-run death of Nathan Haun in Spanish Fork. Witnesses, some reportedly at the behest of their parents, are refusing to tell police details about what happened and who was involved.
As a retired police traffic investigator, I would put all witnesses and their parents in an interrogation room and ask my best potential witness, "What happened and who was driving?" If the witnesses and/or their parents committed the crime of interfering with or hindering in the investigation into the death of a person, the handcuffs would come out and that person would be arrested and taken away.
I would then ask the next person the same question. Believe me, their response would be different. Case solved.