Lets see:
“False Rape Allegations” by Eugene Kanin, Archives of Sexual Behavior Feb 1994 v23 n1 p81 (12), found 41% of all claims over a nine year period were false.
He also studied two state universities and found that 50% of the 64 rape claims were false.
McDowell, Charles P., Ph.D. “False Allegations.” Forensic Science Digest, (publication of the U.S. Air Force Office of Special Investigations), Vol. 11, No. 4 (December 1985), p. 64.
This one found 60% false claim rate.
Here is an online source: http://www.ipt-forensics.com/journal/volume6/j6_2_4.htm.
The percentages are all over the place, but it is clear that false rapes occur frequently. Furthermore, rape is often proved on the basis of one eye-witness’s testimony. As a result, it is impossible to fault a man who records, and keeps private, his sexual encounters.