In what circumstances have courts allowed evidence of criminal activity prior to the murder of a police officer?

In the latter case the defendant, a parolee, and several other defendants, also parolees, were shown, to have engaged in a series or robberies during the four days preceding the murder. They were stopped at a roadblock and were asked for identification. One defendant had none, the officers asked them to get out of the car and in getting out the defendant shot one of the officers. The series of acts which the defendant committed constituted violations of his parole for which he could have been returned to prison to finish out his unexpired sentence and for which new and separate crimes, if apprehended and convicted, he could be sentenced to new and additional terms in prison. 'As each of these criminal acts was committed, the motive to kill to escape apprehension became stronger, because the possible term in prison increased with the commission of each successive act.' (People v. Combes, supra, 56 A.C. 126, at p. 138, 14 Cal.Rptr. 4, at p. 11, 363 P.2d 4, at p. 11.)

'The quantum of evidence, if it is relevant to a fact in issue, does not enter into the question of its admissibility. * * *' (People v. McMonigle, 29 Cal.2d 730, 742, 177 P.2d 745, 752.) In the above cause the court sustained the trial court's admission of evidence of a theft by defendant of a foot locker containing some distinctive clothing some six weeks prior to the murder charged. In that case the relevancy of the theft was to show proof of 'a design or plan to entice' on defendant's part through wearing a serviceman's clothing, and while not admitted on the issue of motive it is pertinent here because of its relevancy to a fact in issue and also because in the Zatzke case (People v. Zatzke, supra, 33 Cal.2d 480, 202 P.2d 1009), as in the case before us, the killing was claimed to have been done in self-defense.