When does AEDPA’s factual-predicate discovery period begin?

Section 2244(d)(1)(D) asks when the claim’s factual predicate could have been discovered through due diligence. Actual discovery alone does not establish that date. Compare the other applicable accrual limbs and qualifying state-review tolling before counting a filing endpoint.

Responsible actor. A state prisoner asserting a federal habeas claim based on an allegedly later-discoverable factual predicate.

Identify the factual predicate of the particular asserted claim, rather than a petition-wide label.

Build a chronology of available evidence, access, reasonable inquiry and actual discovery.

Determine when due diligence could have disclosed the predicate. Do not substitute the day the prisoner first learned its legal significance.

Compare the other statutory limbs and separately establish proper filing and pendency of state collateral applications.

This source guide requires the latest qualifying accrual date, complete review history, claim-specific facts and every supported tolling interval. It supplies no automatic date or paid calculation. A single date cannot establish the limitation period for this procedure.

1. Establish the relevant judgment, asserted claim and governing state-custody or federal-sentence procedure.
2. Compare every applicable statutory accrual limb using the actual review and discovery record.
3. Audit properly filed state collateral applications and their complete qualifying pending intervals.
4. Apply the appropriate time-computation and filing rules only after those legal facts are established.

After establishing the governing accrual event, exclude that event day and examine the corresponding anniversary under the applicable federal time-computation rules. A one-year period must not be replaced mechanically with 365 days across a leap year. This guide does not resolve a February 29 anniversary or supply a running-day ledger. The latest qualifying statutory accrual date and every legally supported excluded interval must be established before arithmetic can represent a filing endpoint. The statutory text does not impose an independent fixed repose date measured solely from conviction. That does not establish that a particular late-discovery claim is timely or otherwise eligible.

Rule 6(a) supplies ordinary weekend, legal-holiday and qualifying clerk-inaccessibility rules where applicable through Habeas Rule 12. Identify the filing district, actual holidays and access facts. A hypothetical Saturday anniversary does not establish the next open filing day in an actual case. A closed-day adjustment cannot itself establish accrual, statutory tolling or equitable relief.

This source guide requires the latest qualifying accrual date, complete review history, claim-specific facts and every supported tolling interval. It supplies no automatic date or paid calculation. A single date cannot establish the limitation period for this procedure.

Assume October 6, 2026 is already established as this claim’s latest qualifying accrual date, with no applicable excluded interval. A corresponding-anniversary illustration reaches October 6, 2027. This arithmetic does not determine whether the assumed legal trigger is correct. October 6, 2027 is an explanatory nominal anniversary only. The guide supplies no automatic filing endpoint.

Assume October 3, 2025 is the established latest accrual date and no excluded interval applies. The corresponding anniversary is Saturday, October 3, 2026. A weekend-only illustration reaches Monday, October 5. Actual district holidays, clerk access and filing facts remain separate checks. Do not publish an automatic Monday filing date without establishing the applicable calendar and all other facts.

Assume the prisoner actually obtains the factual material October 6, 2026, but due diligence could have disclosed it August 6, 2026. Limb (D) asks about August 6 in this hypothesis. An actual-receipt count would use a different event. Other qualified accrual limbs still require comparison. Do not select October 6 merely because it is the actual receipt date.

Assume discovery under limb (D) qualifies on August 6, 2026, but finality under limb (A) qualifies on October 6, 2026. The latest-of comparison selects the later October 6 date between these established candidates. The discovery label does not force the earlier limb. Compare all qualified accrual dates before creating a limitation ledger.

Constructive rather than merely actual discovery

The statutory wording asks when discovery could have occurred through due diligence. An actual receipt date is evidence, not a conclusive substitute.

Four accrual alternatives

Subsection (d)(1) selects the latest applicable limb. A later alleged discovery date must satisfy its statutory conditions.

State review requires proper filing

Pace prevents treating an untimely state application as qualifying statutory tolling merely because it remained on a docket.

Relief needs a separate showing

Holland’s equitable tolling test requires diligence and an extraordinary circumstance that prevented timely filing.

• This source guide requires the latest qualifying accrual date, complete review history, claim-specific facts and every supported tolling interval. It supplies no automatic date or paid calculation. A single date cannot establish the limitation period for this procedure.
• Discovery accrual concerns factual discoverability under limb (D), not direct-review finality under limb (A) or a newly recognized Supreme Court right under limb (C).

• Keep the operative judgment, appellate decisions and applicable review-period evidence.
• Document every asserted claim’s statutory accrual basis and supporting diligence record.
• Record each state collateral application’s proper filing and exact pending interval.
• Check the filing district’s rules, holidays, clerk access and inmate-mail evidence.
• Review second-or-successive restrictions separately from limitation arithmetic.
• The state prisoner files the petition with the appropriate federal district court clerk under Section 2254 Rule 3. For an inmate filing, establish timely deposit, use of the institution’s legal-mail system when one exists, and the required declaration or notarized evidence of deposit and prepaid first-class postage. The date counsel receives a judgment or the date a prison later delivers a paper to court is not a substitute for the applicable trigger or proven filing act.