A leave of court is a legal term used to describe asking the court permission to do something that the court doesn’t normally allow according to its rules and procedures. Either party can file this motion, which is often called a motion for leave. It's commonly used to ask the court to file papers or take some action after a deadline has passed. The party filing the motion has to list a good reason for requesting the court to allow the action out of time, or after the expiration of the date, in order for a court to grant the motion. The party who files the motion often asks the opposing party whether he or she will oppose the filing, and when there is no opposition, the party will indicate so in the motion.
When a court allows the action, then the party can go forward with the court’s permission. It’s often within the court’s discretion to make that decision, but the court usually has to take into account any hardship or prejudice that the other party would suffer as a result and the reason for the motion for leave of court. For example, a court may not grant a lawyer for the defense to file a motion late because he forgot the date. A court may consider a motion if the lawyer submitted an electronic version of a document but encountered technical difficulties in the process.
The other party may oppose a motion and argue that the court should not grant the motion because to do so would somehow prejudice that party’s case or give the motioning party an unfair advantage. The court signs the motion when it makes a decision. The court order is often prepared prior to a decision and submitted by the party filing the motion, along with the original motion. If the court rules in the party’s favor, it often signs the court order that was submitted.
There are a few cases in which the judge is compelled to provide a written opinion for why she grants or denies a motion, but judges often provide no opinion. Some make comments about the motion during a trial proceeding about the motion for leave of court. Either party can ask the court to reconsider its decision on a motion by filing a motion to reconsider.