To my mind, the ACD is more advantageous, as it is not even a guilty plea to anything whatsoever- it is an adjournment, and then a dismissal. The violation, on the other hand, is a guilty plea- usually to disorderly conduct, which is essentially a fictional disposition (penal law 240.20).
The one way the violation may be more advantageous is that the ACD will show up as an open case for the duration of the ACD (6 months or a year, depending). The violation should be immediately sealed.
There is essentially a heirarchy of pleas in cases
an outright dismissal is at the top, with an ACD being next best and then a plea to a violation.
with an ACD you are not pleading guilty to anything.
A violation will be sealed if there is a conditional discharge attached to it, or upon a later motion by you (which would cost money since legal aid would not do such a motion for you)
an ACD is essentially a nice little package that you dont have ot worry about
by the way an ACD period is 6 months generally, and a year in certain cases (such as marijuana).
You will however be limited by what the DA is offering you, and what your defense is able ot secure for you.
there IS however a difference, a huge difference in that one requires you to admit responsibility while the other does not
On the whole, for most people, agreeing to an ACD is preferable to pleading guilty to a violation (or worse.)
The other disadvantage to pleading guilty to a violation is that you will have to pay at least a surcharge, if not a fine also. And ACD, which does not involve pleading guilty and being sentenced, does not carry a fine or surcharge. Both a violation and an ACD can include community service and restitution as part of the disposition.
Some people who need to get a case resolved completely and quickly may choose to take a violation. For instance, if a person is planning on entering the military, an ACD remains open and delays that, while the violation is done once the fine, surcharge and any other conditions are completed. An ACD, i.e., an adjournment in contemplation of dismissal, is a delayed disposition contingent on good behavior, agreed to by the prosecutor, the judge and the defendant. All have to consent to it. If the prosecutor does not want to offer it, he does not have to (except in certain very limited cases.) Some ACDs are for a year. Other people cannot stay out of trouble for six months and for them an ACD is slightly risky; an ACD could be reopened and they could once again be facing the original charge. (That doesn't happen often, but it happens.)
It needs to be noted here that the sealing of either an ACD or a violation will typically not completely hide the existence of these events from criminal justice agencies. Part of the reason for that is that such dispositions may be given to a first time offender, but if you were to commit any offenses later, you would likely not be given the same deal.
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