Definition
An issue that is always resolved by a judge, not a jury, including:
1) An issue regarding the application or interpretation of a law.
2) An issue regarding what the relevant law is. If there are two or more mutually exclusive laws, a judge determines which law is relevant.
3) An issue of fact that nevertheless has been reserved for judges, not juries, to resolve.
Illustrative caselaw
See, e.g. White v. Continental Cas. Co. 878 N.E.2d 1019 (N.Y. 2007).