Fewer women would report rape at all. Making it a crime to report a false rape would only hurt the real victims more, by making it less likely that they will ever try to bring up the charges for fear of a lack of evidence. The majority of rape cases already go unreported and the ones that do usually lack the evidence to bring the accused to court as it is.

Cases like these are exactly why our justice system is not eye for an eye. Revenge is just a knee-jerk reaction. You want to treat the disease? Stop making it so that women are vilified for rape. No more "She was asking for it" bullshit. Teach proper sex ed. There's tons of other things we can do that would be more beneficial than to just lock this girl up.