Why Do Rule 48(a) Dismissals Require “Leave of Court”?

On May 7, the Department filed a motion seeking leave from the district court to dismiss the charges against Michael Flynn. Despite Flynn’s repeated confessions and the district court’s prior rejection of arguments now made in support of Flynn, such as the argument that his lies were not “material” to ongoing investigations, Attorney General William Barr has decided to reverse course.

Rule 48(a) of the Federal Rules of Criminal Procedure provides that the federal government “may, with leave of court, dismiss an indictment, information, or complaint.” So what does it take for a court to grant the government “leave” to