Often, charges are stacked when someone commits a crime. Rarely is it just one crime committed. Example: harassment can also include telephone misuse/misuse of electronic device. Trespassing can happen at the same time as harassment and even stalking.
The problem for the accused is penalties for the crimes. The problem for the prosecution is they may not have enough clear and convincing evidence to get a conviction on a person for all charges the person was arrested for in the first place.
The other part of this takes into consideration whether you are a repeat offender or if this your first time up on these charges. The Courts want to be fair and not slap you with the maximum sentence for all crimes even though they can. That’s not fair to you if the evidence does not support guilt of all crimes. Also, the goal is not to incarcerate, it’s to make you a functional part of society. If you have a chance to be functional, the hope is that you learn your lesson, and don’t commit more crimes.
The prosecutor, too, would rather have a record of your conviction than lose a case because they persisted in trying you on all charges regardless of the evidence they have or didn’t have on you.
So, the plea bargain. In essence, the prosecution makes you a deal: they tell you they know for certain and can prove you are guilty of X lesser charge, and if you plead guilty to that, they will not pursue the other charges in the pile of options they have.
Your lawyer will usually talk some sense to you about taking the deal, because otherwise, you are up on all charges, and this could end badly for you. Pleading guilty is your best bet in getting mercy from the Court in light of evidence against you.
The The Court still takes into account the evidence against you at trial. He or she may punish you within the confines of the charge you plead guilty to. Lesser charge = lesser penalty. The other charges are not “dropped,” they are entered as “nolle prosequi,” which means quite literally “refuse to pursue.” These things remain on the record.
The prosecution and victim get to see you convicted and punished for a crime with your admission of guilt. The case does not drag on forever and expensively for everyone, and everyone just moves on in their life.
Justice is a compromise at times. For the prosecution, a guilty plea is a guaranteed conviction and sentence. Often, prosecutors care whether or not a criminal has a chance to get help. No conviction, no win and no help for the accused.
As a convict, this was a compromise, too. You got your right to a “speedy” trial and unless you’re a repeat offender, didn’t get slapped with the biggest sentence you could have.
Justice is a fluid concept, and it does not mean a person is tried on all charges.