The Speedy Trial Act, 18 U.S.C. §3161 et. seq., provides for specific time limits in which federal prosecutors are to prosecute defendants and bring someone to trial. In general, the federal government must indict within 30 days from the date on which he or she was arrested or served with a summons in connection with federal charges. Also, the federal government must bring the defendant to trial within 70 days of the filing date of the information or indictment or the date of appearance on the information or indictment, whichever date is last. There is a defense preparation period of 30 days during which the defendant may not be tried absent consent in writing. An "arrest" is the actual charging of a federal offense, not simply a detention or charge by state or military authorities.
There are, however, certain exclusions that can extend the 70 day arraignment to trial rule. 18 U.S.C. §3161(h) lists the reasons when the federal government can go beyond the speedy trial time requirements. If the federal government fails to follow the time restrictions of the Speedy Trial Act should result in dismissal of the charges. But even if the court dismisses the charges, many times the federal government if free to bring those charges back.