What is relevant evidence in a murder trial?

evidence tending to show that another person committed the crime, is relevant. But evidence that another person had a motive or opportunity to commit the crime, without more, is irrelevant because it does not raise a reasonable doubt about a defendant's guilt; to be relevant, the evidence must link this third person to the actual commission of the crime. [Citation.] Evidence that is relevant still may be excluded if it creates a substantial danger of prejudicing, confusing, or misleading the jury, or would consume an undue amount of time. (See Evid.Code 352.) (People v. Brady (2010) 50 Cal.4th 547, 558, 113 Cal.Rptr.3d 458, 236 P.3d 312.)