It is very difficult to give you a good answer without a lot more information. Has your husband already been sentenced? If not, has he retained a lawyer? Depending on the facts of the case, he may want to take the case to a bench or jury trial. If he has already reached a plea agreement, any action will have to happen quickly. I recommend you talk to your husband's lawyer or go consult with a local criminal defense lawyer immediately, i.e., today.
It is very difficult to obtain a reduction in a sentence that the person has begun serving.
The reason for this is that, as you describe the situation, the defendant has plead guilty to the charge, and the period of time has passed in which a motion to vacate the guilty plea or appeal the plea or the sentence has passed.
A post conviction motion may be available. Regrettably, this difficult to do and not often granted. Consult an experienced criminal defense attorney who practiced in post conviction situations.
Of course, every answer is based on the question asked and requires a more complete context. This answer should not be relied upon to make a legal decision. Seek the advice of an experienced criminal defense attorney before acting. Law Offices of Raymond G. Wigell, Ltd. Defenders of the Constitution since 1975/ Aggressive Creative Defense Strategies/ Website: www.waaltd.com 24/7 --(708) 481-4800.
It sounds as though your husband entered into what we call a "fully-negotiated plea" of guilty in exchange for the 3-year sentence. There is no getting a sentence reduction from one of these. His only recourse would be a motion asking to withdraw his guilty plea, which opens him up to all he could be charged with and all he could be sentenced to if convicted of those charges. Speak to the lawyer who represented your husband on the plea and if not satisfied ask around. Just beware that a defendant has only 30 days from the date of sentencing to file a motion to withdraw a guilty plea.
This answer is provided for informational purposes only and does not create an attorney-client relationship. Follow-up with a licensed attorney who regularly practices in this field is strongly recommended.