Email asking for money and personal appearance

I got an email from this ACS and have been getting them for three years now. I get them about twice a year. Today I get one and they claim I have to now show up in person in the United States District Court in New York. I called the clerk and have him the case number and he said it was not a legit number and to just ignore them as they are scammers. I said I usually have, but this time they want me to appear in person. he said that was the first time he has heard of that and to call my local police and turn the email over to them. Getting scary now.