What is the test for determining aggravating evidence in a murder trial?

"Aggravating evidence must pertain to the circumstances of the capital offense ( 190.3, factor (a)), other violent criminal conduct by the defendant ( id., factor (b)) or prior felony convictions ( id., factor (c)); only these three factors, and the experiential or moral implications of the defendant's age ( id., factor (i)), are properly considered in aggravation of penalty. [Citations.] Evidence offered as rebuttal to defense evidence in mitigation, however, ...

[51 Cal.4th 223]

need not relate to any specific aggravating factor. [Citation.]" ( People v. Coffman and Marlow (2004) 34 Cal.4th 1, 108-109, 17 Cal.Rptr.3d 710, 96 P.3d 30.)

[51 Cal.4th 223]