Debatable, right? The defense offered this as a possibility, falling back on the valid position that they need offer nothing more. However, other than this statement by the defense attorney there is no evidence to even suggest that this is what happened, and a great deal to suggest that it did not. And while the defense does not have to offer anything, they DO have to offer something if they want the jury to consider it.
The only good news to come out of this is that all of ICA's research and plotting failed to uncover the one method she was almost certain to get away with. All she had to do was take her daughter for a "midnight swim" and leave the sliding door open as she made her way inside alone. Then, no fuss, no bother, the next morning it's "Where's Caylee? She's not in bed! She's not with you?"
No one would criticize HER for no safety locks, it's not her house, there's no case there. At the most someone might try to prosecute ICA's parents, like ICA gives a rip about that, but there's no case there. Caylee was a visitor.
I say good news because had ICA done that Caylee would have gone to her grave and ICA would have gone to her parties, now a victim of tragedy with that to use as a weapon in her con games.