Supposedly, there was a female walking through the alleyway at 9.30 pm, where she spotted a male smoking a cigarette. Being approximately one hour before the screams and possible murder, they obviously would have taken any cigarette butt as valuable evidence, hence it was retrieved. In 1999 it was tested for DNA and yielded a concentration of 0.003 nanograms per microliter. If this female eyewitness was accurate, then this sighting was the last before screams were heard coming from the alleyway, and therefore a credible person of interest in the murder of Cheri Jo Bates. The question is, could forensics separate the sample from the hair at the base of the victim’s right thumb, from DNA retrieved from the cigarette butt.
Whether the cigarette butt originated from the male observed is another matter, but there must have been priority given to any cigarette butt’s near the crime scene, that looked fresh, and still possibly harbored certain quantities of salivary amylase, which is also useful regarding secretors and non-secretors.

Great response, this is exactly the information I was seeking when I asked my question, your response was very helpful and much appreciated.

You figure bates’ murderer might have had to wait around after he disabled the car, and if the killer was a smoker it is entirely possible that while waiting for his victim he smoked a cigarette. Definitely has the potential to be a highly valuable piece of evidence, though I personally think that the "four brown Caucasian head hairs" are still the best evidence.

I’ll do my best to keep up on this topic, thanks for your response.

If Cheri Jo Bates entered the library around opening time, then left shortly after, we obviously have 4 hours to explain.
This man in the alleyway had reasonable vantage point (depending on Terracina Drive streetlights) to view the Volkswagen Beetle parked 75 yards east of the alleyway, just past the library entrance. If Cheri Jo Bates had left the library, say 6.15, and gone elsewhere on foot, leaving her vehicle, then this man in the alleyway (who may have disabled her vehicle) and may have been stalking or targeting her, could likely be under the impression that Cheri Jo Bates was in the library and was due to leave upon closing at 9.00 pm. She however, unknown to him, had gone elsewhere. But he likely knew she had to return sometime to her vehicle. This scenario, however, would indicate a level of persistence on his part, having to have waited upwards of 90 minutes in the area. It’s a possibility, but there are many alternatives in this extremely puzzling case. This is assuming the screams are connected to the murder at a presumed 10.30 pm or thereabouts.

There was a time change on or about the 30th. This change and, additionally, the screams no doubt added confusion to the time estimate. Incidentally, I’ve never understood why those who heard such "terrible" screams didn’t immediately report them to the police. Good, upstanding citizens, huh?

The selfishness of humankind is one possibility. Another, is they mistook the scream for revelers. Today is very different- many eyewitnesses to a crime just start filming it with their smartphone and post it on Youtube for a thumbs up- pathetic really.

If Cheri Jo Bates entered the library around opening time, then left shortly after, we obviously have 4 hours to explain.
This man in the alleyway had reasonable vantage point (depending on Terracina Drive streetlights) to view the Volkswagen Beetle parked 75 yards east of the alleyway, just past the library entrance. If Cheri Jo Bates had left the library, say 6.15, and gone elsewhere on foot, leaving her vehicle, then this man in the alleyway (who may have disabled her vehicle) and may have been stalking or targeting her, could likely be under the impression that Cheri Jo Bates was in the library and was due to leave upon closing at 9.00 pm. She however, unknown to him, had gone elsewhere. But he likely knew she had to return sometime to her vehicle. This scenario, however, would indicate a level of persistence on his part, having to have waited upwards of 90 minutes in the area. It’s a possibility, but there are many alternatives in this extremely puzzling case. This is assuming the screams are connected to the murder at a presumed 10.30 pm or thereabouts.

Again, great response.

The level of persistence required in targeting this victim in the manner which you described is not unreasonable in my mind.

I feel that disabling Cheri Jo’s vehicle was an indication that the killer knew his target, he knew her car, and had likely planned to kill her when she left the library, which makes a scenario in which the killer waited for his victim seem reasonable.

I wish I knew the Cheri jo case better, blue rock springs has taken up a good deal of my focus.

If Mike from the blue rock springs attack was accurately describing events it is possible that Darlene ferrin was followed and stalked prior to her murder, and if we assume that dea and cheri jo had the same killer then this stalking scenario becomes all the more plausible and may even indicate a modus operandi on the part of the killer.

Again, great response, I wish I was better versed in the Cheri jo case. Your responses have been very informative and quite helpful, much thanks.