The most that he could do is send a letter to USCIS, but if you can demonstrate that he is doing that as part of the continued crime/violence, then you should be OK.
Myron R. Morales, Attorney
I agree with Mr. Morales, and I would also suggest contacting either an immigration attorney or accredited representative that can assist you through this process. As the victim of a crime who has suffered physically or emotionally, things are difficult enough for U visa petitioners. Going through the U visa petition process and coming across issues like the one you described can cause extra anxiety, and you may find organizations and attorneys that can help alleviate some of this.
You should review your case with an attorney. I and many others are here in New York should you desire to consult with us.
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