Prior to trial, petitioner believes, the court warned the defense attorneys something to the effect of: “This trial is not going to be about police and prosecutorial misconduct.” The defense was on notice that their entire case plan of putting the system on trial was not to be presented to the jury. Thus, petitioner was without the defense of consent and without the ability to put the police investigation on trial, his right under Kyles v. Whitley (1995) 514 U.S. 419, 445-449, where the U.S. Supreme Court said that the defense can attack the police in front of the jury by cross-examination and in closing argument about shoddy, slovenly, inadequate, or biased police investigation work.
The district court committed plain error and abused its discretion by instructing the jury not to ‘grade’ the investigation
 See also United States v. Hanna (9th Cir. 1995) 55 F.3d 1456, and United States v. Sager (9th Cir. 2000) 227 F.3d 1138, 1145-1146, relying on Kyles. In Sager the court said: “[T]he district court committed plain error and abused its discretion by instructing the jury not to ‘grade’ the investigation.” (Id. at 1145.). “Details of the investigatory process potentially affected [the officer’s] credibility and, perhaps more importantly, the weight to be given to evidence produced by his investigation. Defense counsel may have been fishing for flaws, but it is obvious that he cast his bait in a promising pond.” (Id.) To fail to allow this line of inquiry impinges on a defendant’s state and federal constitutional rights to confrontation and compulsory process. (See Pointer v. Texas (1965) 380 U.S. 400, 403- 405.)
The defense has wide latitude in cross-examination of prosecution witnesses in a criminal case. (People v. Ormes (1948) 88 Cal.App.2d 353, 359; People v. Watson (1956) 46 Cal.App.2d 818, 827.) “We construe the [proper scope of cross-examination], at least ordinarily, that when a prosecution witness testifies to facts tending to establish the guilt of one criminally accused, that witness may be cross-examined on all relevant and material matters preceding, concurring with, or following the criminal event, within his knowledge and reasonably related to the issue of guilt or innocence.” (In re Victor F. (1980) 112 Cal.App.3d 673, 682-683, citing Gallaher v. Superior Court (1980) 103 Cal.App.3d 666, 671.)