The "Balwani abused me and I had diminished mental capacity" is her planned defense in court as stated in the NRP article.

At the trial right now (in court), her lawyers hasn't presented that defense yet. Right now the trial is in the first step, the prosecution/state presenting their case. Once the prosecution/state rests their case, the defense begin present their case (at this point they will present their "Balwami abused me argument".