Like GFactor said, it’s possible there was something in the statute the defense attorney was attempting to disprove or mitigate which could have aggravated or elevated the offense, e.g., perhaps sexual assault by threat of death or serious bodily harm carries a more serious penalty or mandatory minimum. There could be increasing grades of offenses, like indecent sexual contact with a minor, then sexual assault, then aggravated sexual assault, etc., and the defense attorney was attempting to convince the jury that if the defendant was guilty, he was only guilty of one of the less serious offenses.
The other possibility, also mentioned, was that the attorney had no case and had to say something. This is sometimes referred to as the “fetal defense;” curl up into a little ball and let the prosecutor kick the shit out of you until his or her foot gets tired. Put yourself in the position of a defense attorney with absolutely no case: you’ve explained to your client very carefully the evidence against him is very bad, very convincing, and very admissable. You further explain that if he goes to trial, he will be found extremely guilty, will get much worse than what he’s being offered (assuming there even is an offer), and the sentences will be stacked. You do not feel that he will be a very sympathetic defendant and you urge him not to try his luck.
However, the alleged child molester does not seem to have a very good grasp on reality for some reason, and insists contrary to all apparent evidence that the complaining witnesses not only consented, they seduced him. He demands that you mount this defense on his behalf, and if you do not do so adequately, he will take the stand on his own behalf to tell the judge, jury and world how egregiously he has been wronged. No amount of pleading on your behalf can change his mind, and although crazy, your client is neither insane nor incompetent. The decision of whether to proceed with a jury trial is ultimately his, so off you go to fight a very big bear with a very small stick. If all you have is a handful of shit, it’s hard to dress up a shit sandwich.