None of this post is directed at the case in question, as we don't know enough about it yet.
The same opinion must apply to the Mother when a Father kills the Children.
Only it never works like that does it!
It would if the mother abandoned the father and left him to look after the kids on his own.
That's not usually the case though is it? From what I see when a father does that it's usually because he's a self centred bstrd who can't take rejection, takes the kids out for a day and doesn't bring them back, to hurt the mother.

Different motivation entirely.
Women rule the roost when it comes to families. A mother is far more likely to kick out the father than the father leave of his own accord. And the Government will reinforce this. A man is unlikely to steal the kids, but a woman is more likely to block access to the father (for whatever reason), and often out of spite.
If you think women are at a disadvatage in family affairs, how come you don't see hoards of mothers protesting about family law?
Nor do you hear of mothers sat in jail and on hunger strike (fathers who fall behind child support payments in the US can be jailed, and there have been cases of hunger strikes).
Instead, you see them making false accusations for profit, such is the system that enables it. Lawyers get rich, and the father is sent on his way.
I think you'll find that divorce is driven by women, and it is largely frivorlous divorce at that in the main. It is destructive, and the Government support it.
Even if a man wants to have the kids part or full time, it is the mother's choice in the main.
Even if she has a number of kids on her own and she struggles, there are support networks out there to help. Pick up a phone book, and look up mother/women's services. Then look up men's.
Your biase is clear though, and does not stand up to scrutiny, given the ease at which women can eject a man from the home.
Ellel was right, people don't look to blame the mother, but is eager to blame the father. We've seen many times.
The above is a generalisation, but this really does happen with alarming frequency. Fathers are not violent monsters sooey, and mothers are statistically more likely to abuse her children than a father (see also child murder).
See table 4.5 here for stats on child fatalities:
http://oracleofthejedi.blogspot.co..../male-child-abuse-and-fatalities-numbers.html
Or figure 3.6 here:
http://archive.acf.hhs.gov/programs/cb/pubs/cm08/cm08.pdf