Equitable Estoppel

In Washington State, equitable estoppel can sometimes be invoked against a state agency for the actions it takes, but it is generally not applied when the agency's actions are ultra vires (beyond its legal authority—to essentially be void as a matter of law). Courts have ruled that equitable estoppel cannot be used to validate an agency's actions that exceed its statutory authority.

However, there have been cases where courts have considered equitable estoppel in disputes involving state agencies, particularly when individuals relied on agency representations to their detriment, when the agency’s WAC permits such a defense at administrative hearings, such as the Department of Social and Health Services (DSHS), i.e., in a case involving overpayment of public assistance benefits.

If it falls outside of the WAC and is not a result of an administrative hearing, there may still be a remedy in a petition for judicial review with an appellate court.

You should consult with counsel to know what may apply in your particular case.