@boomerang,
Lying is not a crime. Lying under oath, perjury, is the crime, and that was done when she was not an adult.
If the statute of limitations was the real issue I think the prosecutor would have said that.
Normally, the statute of limitations on perjury in that state is 3 years, but I'm not sure whether that would apply in a situation like this--11 or 12 year old children aren't prosecuted under the perjury laws because they aren't held to adult standards of conduct in that regard. A charge of obstruction of justice might also be applicable, but there would be the same problems prosecuting that one because of her age at the time.
As much as many people would like to see this woman punished for what she did to her father, it just might not be legally feasible to do so.
I can't find any info on the father's trial--it would be interesting to know what evidence, beside her testimony, the jury considered.
And, as someone else mentioned in this thread, it is possible that she told the truth in the past and that her now recanting it is the lie--maybe she decided he had suffered enough and this is her way of forgiving him. Her "confession" appears connected to her treatment for drug abuse.
We really don't know enough to draw any firm conclusions.