Here is an article about the case from 2010.
The person that was originally detained for this crime and given a poly test, who was he in relation to the victim? Why we he suspected so early on? I ask because the way in which she was killed and left has similarities with sociopaths that were thrill lust killers of the 70s which means that if he passed the poly as a sociopath, he will feel completely invincible like a superhero or something. So chances are, you may have already missed your prime suspect. Honestly, I hate to say this but I think you would have to take a second look at everything. All evidence, testimonies, witness statements, interviews, everything. There has to be something that was missed in 81 for sure knowing all the we have learned since then.