Federal Rules of Criminal Procedure - Rule 56. When Court Is Open
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(a) In General.
A district court is considered always open for any filing, and for issuing and returning process, making a motion, or entering an order.
(b) Office Hours.
The clerk's office -- with the clerk or a deputy in attendance -- must be open during business hours on all days except Saturdays, Sundays, and legal holidays.
(c) Special Hours.
A court may provide by local rule or order that its clerk's office will be open for specified hours on Saturdays or legal holidays other than than those set aside by statute for observing New Year's Day, Martin Luther King, Jr.'s Birthday, Washington's Birthday, Memorial Day, Independence Day, Labor Day, Columbus Day, Veterans' Day, Thanksgiving Day, and Christmas Day.