After-Acquired Evidence

After-acquired evidence is distinct: it concerns conduct that would have justified termination had it been known.

After-Acquired Evidence is information an employer discovers – typically during discovery in a wrongful termination or discrimination lawsuit – that the employee engaged in misconduct of a nature that would have led to termination had the employer known at the time. Also called: after-acquired evidence doctrine, McKennon doctrine, after-acquired evidence defense.

The McKennon case: facts and ruling

Christina McKennon was a 62-year-old, 30-year veteran of the Nashville Banner Publishing Company who was terminated in 1990 as part of what the company described as a workforce reduction. McKennon sued under the Age Discrimination in Employment Act (ADEA), alleging that the discharge was age-based.

During depositions, McKennon admitted that during her employment she had copied confidential financial records from the company comptroller’s desk without authorization. The company had not known about this conduct at the time of her termination. Upon learning of it during the litigation, the company argued that this after-acquired evidence barred her ADEA claim entirely.

The District Court and Sixth Circuit agreed with the employer. The US Supreme Court reversed unanimously on January 23, 1995. Justice Anthony Kennedy wrote the opinion: after-acquired evidence of employee misconduct that would have resulted in termination does not bar all relief in a discrimination case, but it can limit the remedies available. Where the employer can prove the misconduct and that it would have resulted in termination, back-pay is calculated from the date of the original (discriminatory) discharge to the date the employer discovered the misconduct, rather than running indefinitely. Front-pay and reinstatement are generally unavailable. The discriminatory act remains actionable; the damages are simply truncated.

What the McKennon doctrine actually requires

For an employer to successfully invoke the after-acquired evidence doctrine, several conditions must be met:

• Actual misconduct or material misrepresentation. The employer must prove that the employee actually engaged in the conduct, with admissible evidence. Suspicion or unverified allegation is insufficient.
• Severity that would justify termination. The misconduct must be serious enough that the employer would have terminated the employee for that reason alone, had it been known.
• Actual practice, not just policy. The employer must show that termination is what the company actually does in cases of comparable misconduct, not merely what the policy theoretically permits. Selective enforcement undermines the defense.
• Discovered after the original adverse action. The doctrine only applies to evidence acquired after the termination decision was made.
• Timely assertion in litigation. Most courts have held that the employer must raise the after-acquired evidence defense in a timely manner with adequate factual basis or risk waiver.

Leading examples of misconduct sufficient to invoke the doctrine: material resume fraud, unauthorized copying of confidential records (*McKennon* itself), and serious policy violations such as embezzlement or theft.

How after-acquired evidence affects damages

Why the doctrine matters for HR practice

• Document retention matters. Records of past performance issues, policy violations, and resume statements should be retained for the statute of limitations period plus a reasonable buffer. Lost records cannot become after-acquired evidence.
• Resume verification at hire matters. Background screening that confirms degree, employment history, and certifications reduces the surface area for later “after-acquired” resume fraud cases.
• Honest documentation of termination reasons. When an employer terminates an employee, the documented reasons must be the actual reasons. After-acquired evidence does not retroactively change what the original termination was for.
• Internal investigation discipline. Misconduct discovered during internal investigation should be documented contemporaneously. The documentation supports later use of the misconduct as after-acquired evidence if litigation arises.
• Settlement strategy. The after-acquired evidence defense is often raised primarily for settlement leverage rather than for trial. The presence of credible after-acquired evidence frequently materially reduces settlement value.

Limits and criticisms of the doctrine

• Cannot cure pretext. If the original termination was pretextual cover for discrimination, after-acquired evidence does not retroactively legitimize it.
• State-law variation. California, New York, and several other states have adopted similar but not identical approaches. Multi-state employers cannot assume uniform application.
• Cannot be invented for the case. Discovery-driven “after-acquired evidence” from harassing discovery requests with no good-faith basis can be sanctioned.
• Does not apply to non-discrimination claims uniformly. Application to common-law wrongful termination, breach of contract, and similar state-law claims varies by jurisdiction.

Pair documentation and background screening discipline with structured pre-employment skills assessment that anchors selection in demonstrated capability. See also anti-discrimination and background verification for related frameworks.

Frequently asked questions