You need five years good moral character, or three years if filing based on marriage. If you have had no problems in those 3 years, you should still have no problem. If it was not a "conviction" when you got your green card, it should not be one today either.
The above is intended only as general information, and does not constitute legal advice. You must speak with an attorney to discuss your individual case.
I agree with Mr. Berman ... you will probably be OK.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
You need to establish good moral character for three or five years depending upon the basis for your naturalization application. Assuming you were not convicted and have had no subsequent criminal problems, you should be fine. If you want peace of mind take a copy of the certificate of disposition to an experienced immigration attorney.
The information contained in this answer is provided for informational purposes only, and should not be construed as legal advice on any subject matter. No recipients of content from this answer, clients or otherwise, should act or refrain from acting on the basis of any content included in the answer without seeking the appropriate legal or other professional advice on the particular facts and circumstances at issue from a licensed attorney. Provision of information on this website does not create an attorney-client relationship between you and The Law Offices of Grinberg & Segal, P.L.L.C., nor is it intended to do so.