https://www.ncjrs.gov/pdffiles/dnaevid.pdf

In FBI DNA testing, about 25% of convicted rapists are proved innocent.

https://www.ojp.gov/ncjrs/virtual-library/abstracts/false-rape-allegations

" In the study, 41 percent of the total disposed rape cases were officially declared false."

There is also an Air Force study that said 60% are false, but I can't seem to find it right now.