Just how common is it for Federal Prosecutors to fight AGAINST state court grand juries?
https://www.courthousenews.com/federal-prosecutors-try-to-block-trump-tax-subpoena/
NEW YORK (AP) Federal prosecutors are joining President Donald Trump in asking a federal judge in New York to temporarily block a state court grand jury subpoena seeking his tax returns.
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To the extent that enforcement of the subpoena may adversely affect federal interests of constitutional dimension, those effects could not be redressed after the fact, the prosecutors said in asking for a short stay of the subpoenas enforcement.
Prosecutors say they could inform the judge by next Tuesday whether they intend to join Trumps quest to block his longtime accountant from complying with the subpoena, which stems from a criminal probe.
Manhattan District Attorney Cyrus R. Vance Jr. said Trumps challenge doesnt belong in federal court and hes asked U.S. District Judge Victor Marrero to reject the effort to block the subpoena.