Is assault not a defense to robbery?

Moreover, assault is not a defense to robbery. Generally, defenses fall into two categories: (1) the theory that the evidence is insufficient to establish one of the elements of the offense; or (2) asserting a state of facts that defeats the prosecution allegations. A defense of the first category, insufficient evidence, does not impose a sua sponte duty on the trial court to instruct on that defense if the court has given complete and accurate instructions on the disputed element. (People v. Lawson (2013)

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