Kossen: An AIR21 Same-Action Defense Survived Review

In Kossen v. United States Department of Labor, No. 23-2299 (9th Cir. Oct. 15, 2026), the Ninth Circuit denied a pro se employee's petition for review, affirming a Department of Labor Administrative Review Board (ARB) order that dismissed an aviation whistleblower complaint. The court held that substantial evidence supported the administrative finding that the employer proved its affirmative defense by clear and convincing evidence.

This decision carries clear limits for aviation workers and legal practitioners. First, as an unpublished memorandum disposition under Ninth Circuit Rule 36-3, the opinion does not establish binding precedent. Second, the court's brief ruling does not detail the underlying discharge facts or workplace conduct leading to the dispute. Third, the case involves federal statutory administrative standards under the Wendell H. Ford Aviation Investment and Reform Act for the 21st Century (AIR21), 49 U.S.C. § 42121, not California state law claims under California Labor Code section 1102.5.

How the AIR21 same-action defense works

Under AIR21, federal aviation whistleblower claims follow a two-part statutory burden framework under 49 U.S.C. § 42121(a)(1) and (b)(2)(B). An employee must first show that protected whistleblowing activity was a contributing factor in an adverse employment action, such as a termination. If the worker makes that initial showing, the employer can still avoid liability by proving through clear and convincing evidence that it would have taken the exact same adverse action even in the absence of the protected conduct.

In Kossen, petitioner Darren James Kossen challenged the ARB's dismissal of his retaliation complaint against Empire Airlines, Inc. On review, the Ninth Circuit concluded that substantial record evidence supported the agency's finding that Empire Airlines met this heightened clear and convincing burden (slip op. at 2).

Deference to ALJ credibility and evidentiary rulings

When reviewing Department of Labor administrative decisions under the Administrative Procedure Act, federal appellate courts apply a deferential standard. As established in Calmat Co. v. U.S. Department of Labor, 364 F.3d 1117, 1121 (9th Cir. 2004), the court sustains agency factual findings whenever they are supported by substantial evidence across the administrative record as a whole.

This standard makes challenging an Administrative Law Judge's (ALJ) factual determinations difficult on appeal. Appellate panels grant great deference to an ALJ's credibility findings, upholding them unless they are "inherently incredible or patently unreasonable" (quoting Retlaw Broad. Co. v. N.L.R.B., 53 F.3d 1002, 1006 (9th Cir. 1995)). Furthermore, administrative evidentiary rulings are reviewed for abuse of discretion, requiring a petitioner to show actual legal prejudice before a ruling will be disturbed (slip op. at 2).

Bias allegations and forfeited arguments

The panel also rejected procedural challenges raised by the petitioner regarding judge disqualification and unpreserved arguments. Under Ninth Circuit authority, a party seeking to disqualify an ALJ must demonstrate actual bias rather than mere disagreement with adverse procedural or evidentiary outcomes (citing Bunnell v. Barnhart, 336 F.3d 1112, 1114–15 (9th Cir. 2003)).

Additionally, the court refused to consider arguments that Kossen failed to present before the ARB or raise in his opening appellate brief. Citing 29 C.F.R. § 1979.110(a) and Padgett v. Wright, 587 F.3d 983, 985 n.2 (9th Cir. 2009), the court declined to address those arguments in this petition (slip op. at 3).

Evaluating administrative records in whistleblower disputes

The outcome in Kossen highlights the critical importance of building and preserving an administrative record during agency proceedings. Because federal courts defer to administrative credibility determinations and strictly enforce waiver rules, whistleblower claims often depend on how effectively factual disputes and evidentiary objections are established before the ALJ.

If you are evaluating an administrative agency ruling or seeking guidance on complex retaliation claims, visit our employment litigation page to learn how our firm reviews workplace records and administrative appeal options.