Those seem to me to be the two most obvious motivations. If feeding her by mouth would choke her, well, he was trying to kill her anyway.
Precisely. I hope you don't mind, though, if I repeat my question: can you offer any legitimate motive that would make any sense whatsoever? If not, then I would think it clear that Michael et al. were determined to kill Terri with, at best, craven disregard for whether the facts of the case justified such action.
To my mind, and perhaps some legal experts can chime in on this (IANAL--IDEOPOTV), if someone acts to kill someone with wanton disregard for whether such an act is legally justifiable, such an act should be construed as murder even if there would have been some possibility that the act might not have been. If the killer deliberately destroys any evidence that might mitigate his guilt, such evidence should not be presumed to have been favorable to him.
Do you disagree with my logic?