California Codes, Code of Civil Procedure - CCP, Part 2 — Of Civil Actions, Title 8 — Of the Trial and Judgment in Civil Actions, Chapter 3 — Issues—The Mode of Trial and Postponements, Section 589
An issue of law arises:
(a) Upon a demurrer to the complaint, cross-complaint, or answer, or to some part thereof.
(b) Upon a motion to strike made pursuant to Section 435, 436, or 473.
Notes
Defines an issue of law as arising from a demurrer to a complaint, cross-complaint, answer, or part of one of those pleadings, or from a motion to strike made under any of the three referenced statutory provisions. The definition states those two procedural sources for an issue of law.
Use as reference
Lexinter.net | California Code, Code of Civil Procedure - CCP § 589 | https://laws.lexinter.net/codes/california/code-of-civil-procedure/part-2/title-8/chapter-3/section-589