Whether the 16 year old girl was drunk or not, the two boys shouldn't have taken advantage of her. Even if she wasn't a virgin, which I am not sure of, she should have had the right to say yes or no. The two boys made a conscious decision to have sexual intercourse with an intoxicated minor and they deserve jail time. Serena Williams comments were very much out of line, victim blaming is never okay.
I would never agree with the statement that a rape victim should be partially blamed for a rape. However, people need to take a closer look at how rapes occur. The more vulnerable of a state that you let yourself be, the more likely tragedy will happen to you. It doesn't matter if it's making yourself grossly intoxicated at a party or walking around the wrong side of town all night half naked. You should be able to do those things safely, but in reality you cannot.