The case: Morgan (2002)
Nat'l R.R. Passenger Corp. v. Morgan, 536 U.S. 101 (2002), gave the Supreme Court's clearest answer to a recurring question: when a discrimination claim is built on multiple acts over time, when does the 180/300-day clock start?
The answer splits along the type of claim.
Discrete acts — each one is its own clock
A "discrete act" is a single, identifiable personnel decision: termination, denial of promotion, denial of transfer, refusal to hire, demotion, a specific written disciplinary warning, an individual pay decision. Under Morgan, each discrete act starts its own 180/300-day clock. Acts that fall outside the window are time-barred — but they may still be relevant as background evidence for timely claims.
Practical implication: if you were terminated 200 days ago and your termination followed a year of incrementing discriminatory write-ups, the write-ups themselves are time-barred at the federal level (in a 180-day state). The termination is its own claim with its own clock and may still be timely.
Hostile work environment — one act inside the window saves the rest
Hostile-environment claims are different because, by definition, the environment is created by a series of acts that together produce a hostile condition. Morgan held that a hostile-environment claim is timely so long as any act contributing to the hostile environment falls within the filing window — even if the bulk of the conduct occurred well before that window opened.
The whole environment is treated as a single ongoing unlawful practice. Acts from years earlier are part of the same claim as the most recent contributing act, for both timeliness and damages purposes.
The Lilly Ledbetter paycheck rule
The Lilly Ledbetter Fair Pay Act of 2009 (Pub. L. 111-2) statutorily abrogates the Supreme Court's prior decision in Ledbetter v. Goodyear Tire, 550 U.S. 618 (2007). It establishes that each issuance of a discriminatory paycheck is a fresh "unlawful employment practice" — the clock resets every payday.
The rule applies to compensation discrimination claims under Title VII, the ADEA, the ADA, and the Rehabilitation Act, retroactively to claims pending or filed on or after May 28, 2007.
Importantly, the paycheck rule applies only to compensation discrimination. It does not turn other discrete acts (terminations, denials of promotion) into continuing violations. A termination 200 days ago in a 180-day state is still time-barred at the federal level — the paycheck rule does not help.
Circuit-by-circuit treatment
Federal circuits vary in their application of Morgan's two prongs, especially around:
- What qualifies as a "discrete act" for retaliation claims
- Whether disparate-impact claims follow the discrete-act rule or the hostile-environment rule
- Treatment of constructive discharge (resignation under coerced conditions)
- Application to ADA "ongoing-accommodation" claims
The decoder's continuing-violation toggle surfaces per-circuit doctrine notes based on the state of employment. Circuit-specific application is fact-specific and benefits from attorney guidance.
What this means for your filing date
If your case is built on a series of acts, the federal clock typically runs from the most recent contributing act. The decoder's "date of most recent discriminatory act" field is what governs — use the latest, not the earliest.
When the act type is ambiguous (e.g., a series of write-ups some of which look discrete and some of which look like they contribute to a hostile environment), the timeliness analysis is fact-specific. The decoder surfaces an indeterminate output state in genuinely ambiguous patterns and routes to attorney consultation.