I experienced my first mistrial as a newbie state prosecutor. It was a DUI case. My officer was on cross-examination and the defense attorney was establishing the uniqueness of the Standardized Field Sobriety Tests (SFTs).
After having the officer demonstrate the one-leg-stand, heel-to-toe and finger-to-nose (this was before HGN), the attorney asked if the officer could think of any work, household, or recreational activity that required a person to perform such tasks. The officer said he couldn’t.
Next, the attorney established that when the officer was learning how to administer the SFTs he was allowed to practice numerous times before he was tested because of their uniqueness with which he wasn’t familiar. Furthermore, if an officer didn’t pass the test, they were given remedial instruction and allowed to practice more before they were re-tested.
Then the zinger question, “How many times did you let my client practice these unique tasks before you decided he’d failed, cuffed him, took him to jail, and impounded his car?”
While I hadn’t previously encountered this, I understood it. Counting on the officer to respond that he hadn’t given the defendant any such opportunity, the defense attorney would argue the process wasn’t fair. If jurors believe that, they can find a reason not to convict.
I wasn’t concerned. I knew I could establish on re-direct examination the difference between administering the tests, where we want an officer to demonstrate mastery before he’s authorized to make arrests, and taking the tests, where we don’t want an impaired driver to have multiple tries to hide his impairment. I never got the chance.
In response to the above question, my officer testified, “Your client has practiced at least twice that I know of when I’ve previously arrested him, and he was convicted of DUI.”
“Your Honor! Move for a mistrial!” the defense attorney exclaimed. The judge looked at me with a scowl. I considered responding, “Your Honor, the defense opened the door,” but I knew it wasn’t appropriate. Even if the trial judge sided with me, the conviction would be reversed on appeal. Better to re-try the case the next day with a new jury. “No objection, Your Honor,” I said.
What happened?
I understood Evidence Rule 404(b), but I’d never considered how it might hit a testifying officer like a rear-end collision. From my nearly 40 years working with law enforcement, it appears many prosecutors haven’t considered it — until experience provides a painful lesson.
The rule and its ramifications should be taught in every recruit academy. I subsequently taught it for over 20 years as an adjunct instructor at the Alaska DPS Academy and in my national courtroom testimony training.
For our discussion, Evidence Rule 404(b) prohibits admitting evidence of prior crimes, wrongs, or acts by the defendant other than what he’s on trial for, unless the prosecution moves in advance for its admission. Then the judge must decide whether the evidence meets one of the exceptions in Rule 404(b) and whether its probative value outweighs any prejudice to the defendant.
The rationale behind the rule is that jurors may be prejudiced to convict because of the other bad acts, rather than holding the prosecution to its burden of proving the crimes in the current case.
I’d known about the DUI defendant’s prior record. Given Rule 404(b), I should have warned my officer against mentioning it — no matter what.
Why arguing the defense “opened the door” doesn’t work
Some officers have heard of the defense “opening the door” to inadmissible evidence and ask why that didn’t apply in my DUI case. It’s legalistic, but a defense attorney doesn’t “open the door” simply by asking a question. They only “open the door” when they’ve introduced misleading evidence, and the inadmissible evidence would correct that. Even then, the judge must first weigh the probative versus prejudicial effect of admitting the inadmissible evidence. None of that occurred in my DUI case.
Lessons from the mistrial
First, I explained Evidence Rule 404(b) to my officer, and why his truthful testimony had resulted in a mistrial. The next day, in front of a new jury, I had my officer explain on direct examination why a suspect is not allowed to practice the SFTs or re-take them. There were no questions about it on cross-examination.
After that, I briefed officers on Rule 404(b) before they testified. If there was “prior bad acts” evidence I knew about, I alerted them to it and warned them not to mention it — no matter what.
Many prosecutors haven’t yet learned the painful lesson I did. The takeaway for officers is, before you testify in a criminal case, ask the prosecutor whether there is any Rule 404(b) evidence you should guard against mentioning. You’ll not only impress the prosecutor, you may even teach them they should be briefing witnesses about the rule.
What if the judge orders an officer to answer a question and the response would cause a mistrial? Tune in next month when I’ll share a winning solution to this courtroom dilemma that almost caused a mistrial in a child sexual abuse case.
