I have been doing a little research and found a website written by a homicide and forensic consultant. It's called "The Seven Major Mistakes in Suicide Investigation" but most of the article talks about homicide investigation and how there are cases in which a murderer stages a homicide as a suicide. There is one set of graphic pictures of a homicide staged as a suicide by hanging just to warn anyone who would be disturbed by seeing that.
From the link below:
"The investigator should be aware of three basic considerations to establish if a death is suicidal in nature:
1. The presence of the weapon or means of death at the scene
2. Injuries or wounds that are obviously self inflicted, or could have been inflicted by the deceased
3. The existence of a motive or intent on the part of the victim to take his or her own life"
http://www.practicalhomicide.com/Research/7mistakes.htm
The author goes into detail about each of the three basic considerations and I found it worth the quick read.
I'm still on the fence as to whether this was suicide or homicide but in terms of what info we are aware of at this time, here's my initial response to those three questions, based solely on what has been released:
1. Yes, the means of death was found at the scene and matches with the reported autopsy findings, with the plastic bag being able to cause suffocation and the small amount of water in her lungs.
2. They have stated they found two wounds that were self inflicted, one on each hand, and a razor was found on Cheryl. I would say that yes, Cheryl Had the physical ability to cause those injuries and also could have accomplished the act of placing a plastic bag over her head and laying in the water facedown either by purposely laying facedown, or falling facedown after losing consciousness. I would be more inclined to believe this if toxicology results showed certain drugs in her system, and I'm still not clear on whether or not all toxicology results have come back. My main issue with suffocation from a plastic bag is the body's hypercapnic alarm response which would have triggered her body to get access to oxygen, like ripping the bag off, which she could have done since her hands were not tied. I am still not clear on how the bag was kept in place on her head.
3. I do not know the answer to whether or not Cheryl had a motive or intent to end her life. I'm guessing this is one of the main things investigators are looking at. I hope a thorough victomolgy was being conducted as soon as she was reported missing and continues to be explored.
I think the location of where her car was found and where she was found also needs to be closely reviewed.