While we'd rather be writing that an anti-rape chip had been implanted in all and future persons thereby eradicating the crime, there is a bit of good news to report.
Starting next year, emergency room rape kits -- key for evidence collection should a victim choose to bring charges against an attacker -- will be sealed and stored by number rather than name until used for prosecution. This way, the decision to go to the police or not doesn't need to be made immediately following the trauma of rape. While some states already have similar practices in place, others require police involvement if a rape kit is requested at a hospital.
The US Department of Justice estimates that only 41 percent of sexual assaults today are reported to the police. So, until that chip comes along (and with it, I suppose, the legality of altering free will), perhaps an easier way to collect and preserve evidence will mean more rapists charged and convicted.