If a criminal defendant offers evidence of his or her character circumstantially - to show he or she did not commit the crime charged -- the prosecution can offer rebutting evidence of defendant's character.

Fed. R. Evid. 406 ("regardless of the presence of eyewitnesses").The admissibility of habit does not depend on the presence or absence of eyewitnesses.

Union Mutual Life Insurance Co. v. Chrysler Corp., 793 F.2d 1, 8-9 (1st Cir. 1986) (holding, in plaintiff lending company's action against defendants computer leasing company and another lessee company for breach of lease agreement, that the....A statement is imputed to a principal or to an employer and is treated as the principal's or employer's vicarious admission (which, like other admissions is exempt from the hearsay rule) if the principal or employer is a party, the statement is offered against the principal or party, the statement is a statement by the party's agent or employee about a matter within the scope of the agent's agency or the employee's employment, and the statement is made during the principal-agent or employer-employee relationship.

Buckley v. Mukasey, 538 F.3d 306, 319 (4th Cir. 2008) (vacating judgment and remanding for further proceedings in a retaliation claim in which the trial court excluded Segar litigation evidence, on ground that plaintiff "intended to utilize the Segar litigation evidence to demonstrate retaliatory animus,...Another act, wrong, or crime is admissible to show a motive for some alleged conduct on a particular occasion.