I agree lots of hints can be found by studying clues in murder cases. Can be interesting.
In this case, I'm not yet convinced that Howard did foul play.
The drugs seemed to have killed both Daniel and Anna. I don't think (yet) that Howard gave them drugs to intentionally kill them, but he apparently helped in having drugs available at the house all those years.
And seems like someone on a TV interview said they saw Howard do drugs too. (Hate to post hearsay, but think it's necessary to show drugs were part of their recreation.)
I heard that too. Can't recall where. But mysteriously enough, the media isn't talking about that anymore...hmmmm
KING: Now Lexapro is an antidepressant right?
STERN: Yes, I'm not too familiar with how medications work but, yes, it's an antidepressant.
http://209.85.165.104/search?q=cache:T_X6MEGZQWgJ:transcripts.cnn.com/TRANSCRIPTS/0609/27/lkl.01.html+STERN:+Yes,+I%27m+not+too+familiar+with+how+medications+work+but,+yes,+it%27s+an+antidepressant.&hl=en&ct=clnk&cd=2&gl=us