Analysis of the Expert Witnesses in the Chauvin Trial – P1

Who were the key expert witnesses in the Derek Chauvin trial? (Part I)

A verdict has now been reached in the Derek Chauvin trial, with the officer found guilty of all three charges of second-degree unintentional murder, third-degree murder, and second-degree manslaughter.

Now that the trial is over and justice has been served, Orion Expert Networks (OEN) has taken a look at the witness list to provide you with a prominent example of how important – and even crucial – expert witnesses can be to your case’s success.

While many of the trial’s most-memorable moments were provided through testimony by eyewitnesses such as Darnella Frazier, who recorded the now-infamous video where Floyd yelled “I can’t breathe” as he was pinned down for nine minutes before he died, the lynchpin of the prosecution’s success was the testimony of the many expert witnesses it called to press its case.

Dr. Martin Tobin

Dr. Martin Tobin, an ICU doctor as well as lung expert, provided crucial testimony for the prosecution, saying that Floyd died due to a lack of oxygen caused by Chauvin’s knee putting 90 pounds of weight on Floyd’s neck in three crucial areas, and not the other factors cited by the defense, which argued that drug overdose and a pre-existing heart condition were what killed Floyd, not Chauvin’s nine minutes with his knee on Mr. Floyd’s neck.

But Dr. Tobin was quite successful in batting these down. He said that the drug fentanyl, found in Floyd’s system after his death, couldn’t be its cause, because his breathing was completely normal for most of his detainment (proven by the fact that he was talking up to five minutes in), and that a fentanyl overdose would have stopped the flow of oxygen to the brain much more quickly.

The rest of Tobin’s testimony was similar: professional. Full of incontrovertible facts. Unemotional, but not cold. And, perhaps most importantly, Tobin was excellent at explaining these scientific and medical facts to the jury in a way that they – a cross-section of society – could understand easily. The jury’s ability to understand well and without too much mental athletics why it was unquestionably Chauvin’s knee that caused Floyd’s death, and that, by the laws of medical science, fentanyl and his heart condition couldn’t have been the causes of his death, were crucial to the verdict.

The prosecution obviously chose Dr. Tobin, a doctor from Chicago, because its research provided it with the sense that he would be able to get through to the jurors better than other, say, Minneapolis pulmonologists. Because in a less high-stakes case, it may very well have been more important to choose a respected local figure than one who possessed Tobin’s unique skills. Local connections can be incredibly important in expert-witness selections, but in this case they clearly weren’t when compared to the option of Tobin.

Here at Orion Expert Network, we conduct this sort of research and analysis for you, providing you with the benefit of our knowledge, experience, and connections to ensure that your other responsibilities in a trial – submission of briefs, jury selection, etc – can take up more of your precious time with the knowledge that a dedicated and specialized team is hard at work selecting expert witnesses for you.

Barry Brodd

Perhaps the most useful performance for their case among the defense’s witnesses was Barry Brodd’s, who was the first use-of-force expert in the Chauvin trial to say that the officer’s action of keeping his knee on Floyd’s neck was justified.

Because the police sometimes deal with very dangerous situations, they sometimes need to make quick decisions about what to do with a suspect, with no other guide than their own experience and training. While almost all experts agreed that police need at least some longitude to react to a suspect’s actions, Brodd said first and most convincingly what no prosecution use-of-force expert would say: Chauvin’s reactive choices that day were well-intentioned and even justified by his training.

Brodd argued that Chauvin’s alleged use of force was not necessarily an example of use of force at all. He claimed that the position used by Chauvin on Floyd was thought by many to be painless, which would take it out of this category. If the jury viewed Chauvin’s actions as justified or possibly justified, he would have walked. Brodd’s testimony gave the prosecution a shot at acquittal.

Unfortunately for the defense, Brodd, a former police detective from Santa Barbara, California, had fewer facts on his side than did the prosecution. Brodd was probably selected as an expert witness specifically because of the professional opinion he was able to offer to the jury. He, like Tobin, was selected from far outside Minneapolis, likely for reason alone that he held the opinion that the defense needed in order to win its case. That Brodd was not a higher-up official or from a more prominent institution was likely not lost on the jury, which sided with the prosecution. (Almost all of the Minneapolis police officers who testified did, as well.)

Brodd, perhaps in part because of his lower-level qualifications and experience, but also because of the unfavorable set of facts and cross-testimony he was presented with, did not handle questioning nearly as well as Dr. Tobin. When he was asked if the prone control position could be considered a use of force where the suspect was compliant, he conceded that it could, which added to the questions the jury had to consider about the case: was Floyd compliant? Judging by his actions in the smartphone video, he was.

This is not to knock the defense’s preparation work on Brodd. Because of the highly charged and controversial nature of the trial, as well as the evidence, it was likely very difficult for them to find witnesses to support their case. Brodd may very well have been the best out of the few. But were there possibly other, better options? Sure.

With Orion Expert Network, you won’t have to wonder if you’ve considered all the angles. You’ll possess the security that comes from having our dedicated team of experts consider potential witnesses against the dynamics of your case, based on our extensive knowledge of, and personal relationships with, experts over many different matters. This gives us a much better sense than you would have merely interviewing your witness once or twice before selection. Everyone tries their hardest during job interviews, and the questioning isn’t nearly as rigorous as those given during a trial.

In our next post, we’ll continue our analysis of the expert witnesses in the Chauvin trial, with analysis of the experts Dr. David Fowler, Minneapolis Chief of Police Medaria Arradondo, and police officer Nicole Mackenzie.

Authored by:

Mike Dubois, JD
Orion Expert Network

Summary of Federal Rules 701-706

Rule 701. Opinion Testimony by Lay Witnesses

If a witness is not testifying as an expert, testimony in the form of an opinion is limited to one that is:

(a) rationally based on the witness’s perception;

(b) helpful to clearly understanding the witness’s testimony or to determining a fact in issue; and

(c) not based on scientific, technical, or other specialized knowledge within the scope of Rule 702.

(Pub. L. 93–595, §1, Jan. 2, 1975, 88 Stat. 1937; Mar. 2, 1987, eff. Oct. 1, 1987; Apr. 17, 2000, eff. Dec. 1, 2000; Apr. 26, 2011, eff. Dec. 1, 2011.)

Rule 702. Testimony by Expert Witnesses

A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:

(a) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;

(b) the testimony is based on sufficient facts or data;

(c) the testimony is the product of reliable principles and methods; and

(d) the expert has reliably applied the principles and methods to the facts of the case.

(Pub. L. 93–595, §1, Jan. 2, 1975, 88 Stat. 1937; Apr. 17, 2000, eff. Dec. 1, 2000; Apr. 26, 2011, eff. Dec. 1, 2011.)

Rule 703. Bases of an Expert’s Opinion Testimony

An expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. If experts in the particular field would reasonably rely on those kinds of facts or data in forming an opinion on the subject, they need not be admissible for the opinion to be admitted. But if the facts or data would otherwise be inadmissible, the proponent of the opinion may disclose them to the jury only if their probative value in helping the jury evaluate the opinion substantially outweighs their prejudicial effect.

(Pub. L. 93–595, §1, Jan. 2, 1975, 88 Stat. 1937; Mar. 2, 1987, eff. Oct. 1, 1987; Apr. 17, 2000, eff. Dec. 1, 2000; Apr. 26, 2011, eff. Dec. 1, 2011.)

Rule 704. Opinion on an Ultimate Issue

(a) In General—Not Automatically Objectionable. An opinion is not objectionable just because it embraces an ultimate issue.

(b) Exception. In a criminal case, an expert witness must not state an opinion about whether the defendant did or did not have a mental state or condition that constitutes an element of the crime charged or of a defense. Those matters are for the trier of fact alone.

(Pub. L. 93–595, §1, Jan. 2, 1975, 88 Stat. 1937Pub. L. 98–473, title II, §406, Oct. 12, 1984, 98 Stat. 2067; Apr. 26, 2011, eff. Dec. 1, 2011.)

Rule 705. Disclosing the Facts or Data Underlying an Expert’s Opinion

Unless the court orders otherwise, an expert may state an opinion—and give the reasons for it—without first testifying to the underlying facts or data. But the expert may be required to disclose those facts or data on cross-examination.

(Pub. L. 93–595, §1, Jan. 2, 1975, 88 Stat. 1938; Mar. 2, 1987, eff. Oct. 1, 1987; Apr. 22, 1993, eff. Dec. 1, 1993; Apr. 26, 2011, eff. Dec. 1, 2011.)

Rule 706. Court-Appointed Expert Witnesses

(a) Appointment Process. On a party’s motion or on its own, the court may order the parties to show cause why expert witnesses should not be appointed and may ask the parties to submit nominations. The court may appoint any expert that the parties agree on and any of its own choosing. But the court may only appoint someone who consents to act.

(b) Expert’s Role. The court must inform the expert of the expert’s duties. The court may do so in writing and have a copy filed with the clerk or may do so orally at a conference in which the parties have an opportunity to participate. The expert:

(1) must advise the parties of any findings the expert makes;

(2) may be deposed by any party;

(3) may be called to testify by the court or any party; and

(4) may be cross-examined by any party, including the party that called the expert.

(c) Compensation. The expert is entitled to a reasonable compensation, as set by the court. The compensation is payable as follows:

(1) in a criminal case or in a civil case involving just compensation under the Fifth Amendment, from any funds that are provided by law; and

(2) in any other civil case, by the parties in the proportion and at the time that the court directs—and the compensation is then charged like other costs.

(d) Disclosing the Appointment to the Jury. The court may authorize disclosure to the jury that the court appointed the expert.

(e) Parties’ Choice of Their Own Experts. This rule does not limit a party in calling its own experts.

(Pub. L. 93–595, §1, Jan. 2, 1975, 88 Stat. 1938; Mar. 2, 1987, eff. Oct. 1, 1987; Apr. 26, 2011, eff. Dec. 1, 2011.)


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