I have a similar theory: Casey chloroformed Caylee and put her in the trunk, with tape over her mouth in case she woke up, while partying. Caylee either died of chloroform overdose or carbon monoxide.
Bottom line:
1) Such plausible scenarios make it difficult to prove murder when there is no cause of death.
2) Casey technically didn’t “kill” Caylie, but was certainly complicit - is her attorney parsing words?
This is possible, sure.
"Bottom line:"
"1) Such plausible scenarios make it difficult to prove murder when there is no cause of death."
Not in this case because that still would have been murder.
"2) Casey technically didn’t “kill” Caylie, but was certainly complicit - is her attorney parsing words?"
But if she did what you describe then she did kill her. I don't just mean by some legal definition either. If she did those things that caused Caylee's death, then she killed her.