A defendant should be entitled to have a jury consider whether a cop seeking a warrant actually had a good faith belief that it would turn up particular evidence of a particular crime, and that all the evidence given to the warrant judge was truthful. Note that a meaningful inquiry into such a question may entail evidence from witnesses who had never been cross-examined prior to their appearance in trial court, so the fact that a judge signed off on a warrant does not imply that it was in fact issued on the basis of probable cause. Suppose, for example, that Officer Jones got a warrant for some address on the basis that drug activity had been observed there two months ago, but on cross examination in trial court he admitted that six weeks ago the landlord had called police to clean up a meth lab left by an evicted tenant, and he (Officer Jones) had been involved with the cleanup. Would not a defendant have the right (whether or not a judge would allow it) to have the jury consider whether Officer Jones really had good faith probable cause?
BTW, I would aver that for a judge should censor truthful arguments by the defendant is an abrogation of the right to jury trial. If an omniscient jury would acquit someone, but a judge withholds information from that person's jury so as to score a conviction, then the defendant's guilt wasn't decided by a jury--it was decided by the judge. For that matter, if a defense wants to argue that the jury should acquit him because the weight of the defendant's knife, in grams was less than the weight of a steam locomotive in ounces, the defense should be allowed to argue that, provided that (1) the defendant is personally willing to waive any claim of inadequate counsel, and (2) the prosecution is then allowed to inform the jury that there is no statutory relevance to the relative weight of the items in question. The jury should be entitled to make of the argument what they will. Most of the time, statutorially-baseless arguments will do nothing but annoy the jury. On the other hand, on those occasions where a jury would find a particular truthful argument compelling, such a finding would imply its relevance.
The second paragraph has to do with how a trial is structured. Sometimes a defendant is prevented from telling the jury about relevant law, too. The system viciously guards its power, but generally has a good faith conviction that the structure of the trial allows for all the relevant information to be presented to the jury.
The case that I have in mind about the law is a defendant being prevented from showing the jury the controlling US Supreme Court precedent, Miller v. US. He was allowed to present that to the judge, but the courts are corrupt on 2nd amendment law.