Equitable tolling is a principle of law stating that a statute of limitations

Statute of limitations

A statute of limitations is an enactment in a common law legal system that sets the maximum time after an event that legal proceedings based on that event may be initiated...

 shall not bar a claim in cases where the plaintiff

Plaintiff

A plaintiff , also known as a claimant or complainant, is the term used in some jurisdictions for the party who initiates a lawsuit before a court...

, despite use of due diligence

Due diligence

"Due diligence" is a term used for a number of concepts involving either an investigation of a business or person prior to signing a contract, or an act with a certain standard of care. It can be a legal obligation, but the term will more commonly apply to voluntary investigations...

, could not or did not discover the injury until after the expiration of the limitations period. When the United States is a defendant, equitable tolling cannot be applied against the United States since the Spending Clause has been interpreted by the Supreme Court to only vest Congress with the authority to waive sovereign immunity, and statutes of limitation are interpreted as a condition on the waiver of sovereign immunity

Sovereign immunity

Sovereign immunity, or crown immunity, is a legal doctrine by which the sovereign or state cannot commit a legal wrong and is immune from civil suit or criminal prosecution....

 that limit the jurisdiction

Jurisdiction

Jurisdiction is the practical authority granted to a formally constituted legal body or to a political leader to deal with and make pronouncements on legal matters and, by implication, to administer justice within a defined area of responsibility...

 of a court to hear cases against the United States.

For example, when pursuing one of several legal remedies, the statute of limitations on the remedies not being pursued will be equitably tolled if the plaintiff can show:

• Timely notice to the adverse party is given within applicable statute of limitations of filing first claim
• Lack of prejudice to the defendant
• Reasonable good faith conduct on part of the plaintiff.