(dissenting).
I respectfully dissent from Division II and the result because I believe trial court *587erred in overruling defendant’s motion for mistrial.
The exceptional cases where the striking of improper testimony is not adequate to avoid prejudice include situations where the prejudice inherent in the testimony is so great it is unreasonable to believe the jury would disregard the objectionable matter despite an instruction to do so. State v. Ware, 205 N.W.2d 700, 705 (Iowa 1973). Those situations may arise, as in the present case, through the fault of no one. This contrasts with situations where prejudice occurs through prosecutorial persistence. State v. Jensen, 216 N.W.2d 369, 374 (Iowa 1974); State v. Wright, 203 N.W.2d 247 (Iowa 1972).
Here the witness blurted out that she knew defendant “was a known heroin dealer.” Defendant was on trial for possession of heroin with intent to deliver. This is equivalent to a witness saying in a murder prosecution that the defendant is a “known murderer” or in a larceny prosecution that the defendant is a “known thief.” Such statements are calculated to encourage conviction of a defendant because of bad character rather than proof he committed the offense charged. Character and reputation evidence can be introduced by the State under well-defined limitations only after a defendant puts his character in issue in a case. State v. Osborne, 200 N.W.2d 798, 808 (Iowa 1972); State v. Hobbs, 172 N.W.2d 268, 271 (Iowa 1969). “A defendant must be convicted only if it is proved he committed the offense charged and not because he is a bad man.” State v. Wright, supra, 203 N.W.2d at 250.
I do not know why the trial judge can be said to have a vantage point superior to ours by which to gauge the effect of objectionable matter on a jury. The issue of prejudice must be evaluated objectively by examination of the improper testimony, not subjectively by attempting to psychoanalyze the jury. Trial court discretion operates within limits. “It must be utilized fairly and impartially, not arbitrarily, by application of relevant * * * principles to all known or readily available facts of a given issue or cause to the end that justice may more nearly be effectuated.” State v. Vickroy, 205 N.W.2d 748, 751 (Iowa 1973); see generally K. Dunahoo, The Scope of Judicial Discretion in the Iowa Criminal Law Process, 58 Iowa L.Rev. 1023.
The improper testimony in the present case was inherently prejudicial, and I believe the prejudice was so great we cannot reasonably say it was dissipated by the trial judge’s request that the jury disregard the statement. To say otherwise is to deny as judges what we know as human beings.
I would reverse.
MASON, RAWLINGS, and REY-NOLDSON, JJ., join in this dissent.