Rather than depending on government to prevent another tragedy such as Caylee Anthony's, I would suggest a proactive solution based on the way we teach young sailors in our Junior Fleet sailing class. We make it a rule that the kids always wear their lifejackets with a whistle attached. The only time they are allowed to remove their lifejacket is when they are under direct adult supervision. They are allowed to swim without their lifejackets only when an adult is there and watching them.
This way the kids develop good habits. And they know that if they blow their whistle, it means they need help, right now. Screaming can be a result of reacting to being splashed or other typical kids' behaviors. Blowing the whistle is a deliberate act. We also teach them to take a deep breath and hold it whenever they feel like they are going to fall into the water. This prevents them from gasping with their faces in the water. If their lungs are already full, they cannot inhale more air or water. So when they bob to the surface, they are instructed to blow their whistles. This proves that they have only air, not water, in their lungs and alerts anyone around that they might need help. The kids find this drill to be fun! Take a deep breath, jump in and blow your whistle immediately as you surface. Try it! Your kids will thank you by learning to help themselves.
Consider if Caylee Anthony had been trained this way and did indeed go into the pool unattended, as Casey alleged. She still would not have been able to get out, but wearing her lifejacket, she would not drown. And by blowing her whistle, she might have drawn the attention of a responsible adult neighbor, as her adult guardian proved herself to be absolutely worthless when Caylee needed her. Caylee definitely would have had a much improved chance for survival. And she would bequeath a noble legacy to other children.