After holding a U.S. green card (lawful permanent residence) for several years and learned English reasonably well, it's normally a good time to start thinking about applying for naturalized U.S. citizenship. However, if you are on probation for a crime, doing so now would be likely be wasting your time, as explained below.
A person who, after being convicted of a crime, is placed on probation or parole, or has a suspended sentence, must successfully complete it in order to be approved for U.S. citizenship. This comes from the U.S. Citizenship and Immigration Services (USCIS) regulations at 8 C.F.R. § 316.10(c)(1).
There are no exceptions to this rule. A citizenship application will simply not be approved while you are on probation or parole—no matter how minor the crime. USCIS will either postpone a decision on your application until your probation or parole is completed or ask you to reapply later.
Even after you have completed your probation, your troubles might not be over. You will need to look into whether the crime you committed could result in the U.S. government taking away your green card, as covered Crimes That Will Make an Immigrant Deportable.
And even if you dodge that bullet, you will need to find out whether the crime bars you from receiving U.S. citizenship, or might cause the USCIS examiner to deny you based on lack of good moral character, as described in Crimes That Will Prevent You From Receiving U.S. Citizenship.
An experienced attorney can assist with the task of figuring out your eligibility for U.S. citizenship, including when would be best to apply; and assist with the paperwork.
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