Ab initio

What ab initio means

In short, ab initio is a term you will meet in court papers, rules and legal research. The definition above gives its usual meaning in American civil practice. However, the exact meaning can depend on the rule, statute or court decision that uses it. So it helps to read the term in context.

Where ab initio comes up

For example, the term appears in these procedures:

• Motion to Vacate Judgment (Fed. R. Civ. P. 55(c), 59(e), 60(a)–(c)): a motion asking the court to cancel (vacate) a judgment it has entered. In federal court there is no single "motion to vacate" rule; the right rule depends on how much time has passed and why the judgment is being challenged.

How to research the term

Start with the primary source. For example, if ab initio appears in a federal rule, read the rule itself and its official notes. After that, check your court’s local rules and any standing orders from the judge. In addition, search recent decisions from your own state or federal district. They show how courts read ab initio in practice. Because state rules often differ, our state procedures guide links to each state’s official rules. Above all, make sure the version you read is still in force.

You can read the official rule text online for free.

Related legal terms

• Void: having no legal effect from the beginning, as if it never existed.
• Absurdity doctrine: the canon that courts avoid reading a statute in a way that produces absurd results.
• Abuse of discretion: a standard of review under which an appellate court reverses a trial court's discretionary decision only if it was clearly unreasonable, rested on a legal error, or relied on clearly wrong findings. Many rulings on evidence, discovery and case management are reviewed for abuse of discretion.
• Accept: to agree to an offer or to take something as given.

Why precise terms matter

Courts read legal terms closely. As a result, knowing the exact meaning of a word helps you follow orders, rules and filings. Each glossary entry on Lawtopolis is short on purpose and links to the pages where the term is used.