What is the test for making a new argument in a reply brief on appeal?

Appellant presents a new argument in her reply brief on appeal. She argues that due to her memory loss, she was entitled to a presumption of due care. Normally this court does not consider arguments made for the first time in a reply brief on appeal absent a showing of good cause for not presenting such arguments earlier. (Allen v. City of Sacramento (2015) 234 Cal.App.4th 41, 52.) The reason for this rule is fairness -- it is unfair to allow a party to withhold a point until the closing brief, which deprives the opposing party of the opportunity to file a written response unless supplemental briefing is ordered. (Ibid.) To be thorough, we have permitted respondent to file a supplemental brief concerning appellant's new evidentiary argument, which we briefly address.

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