Does the secondary evidence rule apply to the content of a letter?

exclude secondary evidence of the content of writing if the court determines either of the following: [] (1) A genuine dispute exists concerning material terms of the writing and justice requires the exclusion. [] (2) Admission of the secondary evidence would be unfair." Enacted in 1998and thus applicable to defendant's 2001 trialthe secondary evidence rule replaced the best evidence rule, which was repealed. "Under the secondary evidence rule, the content of a writing may now be proved either by an otherwise admissible original ( [Evid. Code,] 1520 or by otherwise admissible secondary evidence ( [Evid. Code,] 1521, subd. (a) ; [citation] ).") (People v. Goldsmith (2014) 59 Cal.4th 258, 269, 172 Cal.Rptr.3d 637, 326 P.3d 239.)