Anderson v. State, 372 P.3d 263

Mark D. Anderson was tried and convicted of ten counts of sexual abuse of a minor based on testimony from three different victims; the jury acquitted him on one count.
Each victim testified to multiple, distinct acts over months and at various locations; the trial court did not give a factual-unanimity instruction (requiring the jury to agree on which specific act supported each conviction).
Defense counsel did not request the factual-unanimity instruction at trial; Anderson raised the issue on appeal.
The court of appeals (Anderson I) found the omission was error but reviewed for plain error because there was no contemporaneous objection and concluded the error was harmless beyond a reasonable doubt, affirming the convictions.
The Alaska Supreme Court granted review, remanded for supplemental briefing on whether counsel’s omission was tactical and on which harmless-error approach to apply (guilt‑based vs. effect‑on‑the‑jury); the court later again took review to address the appellate approach but ultimately dismissed the petition as improvidently granted, adopting the effect‑on‑the‑jury standard and declining to reverse.

Issue	Anderson's Argument	State's Argument	Held
Whether failure to give a factual‑unanimity instruction was reversible error	Trial court erred by not requiring juror agreement on specific acts supporting each conviction	Error occurred but should be reviewed for harmlessness because no objection was made at trial	Court treated it as constitutional error but assessed under plain‑error harmlessness review
Whether counsel’s failure to object was tactical (affects plain‑error analysis)	Counsel’s omission might not be tactical; remand needed to determine intent	Argued omission was not a waiver of review of error; both parties briefed tactical‑decision question	Court of appeals was asked to consider whether omission was tactical; Supreme Court found no reversible error on remand
Harmless‑error standard to apply (guilt‑based vs effect‑on‑the‑jury)	Effect‑on‑the‑jury approach better captures whether error actually influenced jury	Agreed Alaska follows effect‑on‑the‑jury and not a guilt‑based outcome test	Alaska Supreme Court adopted the effect‑on‑the‑jury approach for prejudice analysis
Whether convictions must be reversed under effect‑on‑the‑jury harmlessness review	Error was not a substantial factor in the verdict; convictions stand	Error was harmless beyond a reasonable doubt under effect‑on‑the‑jury analysis	Court affirmed (dismissed petition as improvidently granted) and did not disturb the court of appeals’ harmless‑error conclusion

Anderson v. State, 289 P.3d 1 (Alaska App. 2012) (court of appeals decision finding factual‑unanimity instruction error)
Anderson v. State, 337 P.3d 534 (Alaska App. 2014) (court of appeals opinion on remand affirming convictions and harmless‑error analysis)
Adams v. State, 261 P.3d 758 (Alaska 2011) (plain‑error test elements including prejudice/harm standard)
Nader v. United States, 527 U.S. 1 (1999) (U.S. Supreme Court discussion of harmless‑error standards)