What is the test for exclusion of witnesses from testimony in a sexual assault trial?

[W]hether the exclusion of [witnesses'] testimony violated [defendant's] right to present a defense depends upon whether "the omitted evidence [evaluated in the context of the entire record] creates a reasonable doubt that did not otherwise exist." In a close case, "additional evidence of relatively minor importance might be sufficient to create a reasonable doubt." On habeas review, trial errors are subject to lenient harmless error review. The creation of otherwise non existent reasonable doubt satisfies the "substantial and injurious" standard [of Brecht v. Abrahamson, 507 U.S. 619 (1993)].

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