Presumably. We know he once had a job as a police dispatcher so he definitely knows that 911 calls are recorded and played in open court during a trial. It's certainly convenient that he made sure he didn't make that call.
Presumably he also knows that 911 calls can prove very problematic for criminals when they are the ones making the call.
Darlie Routier comes instantly to mind, that 911 call, definitely played more than a little part in her conviction.
I am having a lot of trouble with the internet searches, assuming they did, in fact, take place. I cannot see any innocent reason for them.
The idea that he was "worried" about it, so he needs to research it? I am not buying that. If you are worried it could happen to you, you look for ways to avoid it. Someone mentioned the idea that you put your shoe in the backseat when your child is in the carseat. Whatever. That is the type of thing you would be looking for. Not "how long" it would take to kill your child.
You know it is going to kill your child. What difference would it make how long it would take? You simply wouldn't do it.
If you are afraid of your infant suffocating , are you going to research how long it would take for them to suffocate? How about you reseach how to avoid it?