SMH. The courts aren't going to make the distinction. The charge of false allegations needs to have proof to convict the same as convicting a rapist. Except of course, it's easier to prove rape than prove not rape. Look, all I'm saying is that if it's proven that a false allegation is made that could've resulted in an innocent having their life ruined, the punishment should be the same. Not a mistaken allegation, not a not guilty verdict but a false allegation. To convict on a false allegation, it has to be beyond a reasonable doubt, same standard for convicting on rape. You seem to think imprisoning an innocent on rape is better than a rapist going free. The "innocent until proven guilty" standard that this country's justice system has been based says otherwise for good reason.
Also, you do realize that evidence can exist for rape when a rape never occurred. If the "she said" is all it takes then you're handing one hell of a weapon to any woman who wants revenge against her cheating boyfriend or wants to blackmail someone for money. Even if no physical act took place, disgruntled women employees have used the allegation of sexual harassment to either get even with or extort money from their employers.
Just like you want to deter rapists, you should also want to deter the false allegations just as much. And I'd rather be falsely accused of mugging someone than of rape and that's why there needs to be different degree of false accusations just like there are different degrees of other crimes.