Cal. Rev. & Tax. Code § 24360
In the case of any bond, as defined in Section 24363, the following rules shall apply to the amortizable bond premium (determined under Section 24361 on the bond):
# (a)
In the case of a bond, the amount of the amortizable bond premium for the taxable year shall be allowed as a deduction.
# (b)
In the case of any bond the interest on which is excludable from gross income under Chapter 3 (commencing with Section 23501), no deduction shall be allowed for the amortizable bond premium for the taxable year.
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