Let only she who is without sin make a rape accusation?

I'm sorry to see the case against DSK collapsing because the alleged victim has been found to have lied in the past. Is it any less wrong to decide she must be lying now because she lied before, than to decide he must be guilty now because he's been known to have harassed other women? Further reading - Dominique Strauss-Kahn: prejudice and politics shape a rape case again and What Strauss-Kahn and His Accuser Risked.