Derek Chauvin trial: officer’s brief defense could reflect confidence ... or lack of credibility

The prosecution took 10 days to lay out its case against Derek Chauvin. The former Minneapolis police officer’s defense to the charges of murdering George Floyd barely lasted two.

The relative brevity of Chauvin’s case might reflect a confidence on the part of the defense that the evidence against him is easily picked apart or at least shaky enough to raise reasonable doubt with the jury.

Or it may have been the result of difficulty in finding credible witnesses to argue that Chauvin not only did nothing wrong but that, in any case, his actions did not kill Floyd.

At the end of the third week of the trial, all that is left is for each side to make their closing statements and the jury to consider whether the evidence is sufficient to convict Chauvin of murder, manslaughter or neither over the death of the 46 year-old Black man in Minneapolis nearly a year ago.

Related: George Floyd killing: defense rests case after Derek Chauvin declines to testify

The defense challenge was to pull apart the narrative built by the prosecution around more than nine minutes of video showing Chauvin with his knee on Floyd’s neck. The video that shocked millions of Americans, and prompted racial justice protests around the world, was shown repeatedly in court and the jurors appeared intently focussed and pained by it each time.

Prosecutors called a train of experts to build their case that Chauvin was responsible for “grinding and crushing (Floyd) until the very breath, the very life, was squeezed out of him”. For 10 days the jury heard from Chauvin’s police colleagues, medical experts, and passersby who pleaded in vain for Floyd’s life.

Prosecutors constructed a detailed narrative, evidently intended to fend off each potential defense challenge, as they painted the accused police officer as going rogue and his actions as the direct and only cause of Floyd’s death.

The defense’s biggest challenge was perhaps the medical evidence after a series of medical specialists testified that Floyd could not breathe under the crushing weight of the police officers on top of him. One said the effect was the same as losing a lung which caused brain damage and then death. Other experts told the jury that while the detained man had illicit drugs in his system, the amounts were nowhere near enough to kill him.

Against all of this, the defense, perhaps surprising, called a lone medical expert: Dr David Fowler, Maryland’s former chief medical examiner.

Fowler said the prosecution witnesses had got it all wrong. He claimed that Floyd was killed by an enlarged and damaged heart affected by drug use. But he said that because his death could not be narrowed down to a single cause, it should be declared “undetermined”.

Fowler also introduced the novel idea that vehicle exhaust may have played a part in killing Floyd by raising the amount of carbon monoxide in his blood and affecting his heart. He said he specifically eliminated asphyxia as a cause of death.

But, crucially, Fowler was forced to acknowledge that the police “restraint” played a part in bringing on Floyd’s cardiac arrhythmia – an implicit admission that he would not have died at that time but for the arrest.

Prosecutors would no doubt like to have told jurors that Fowler has a controversial history.

The retired medical examiner is being sued for certifying that a Black teenager with bipolar disorder died from natural causes after being held facedown by three Maryland police officers. The American Civil Liberties Union has accused Fowler of “creating false narratives about what kills Black people in police encounters”.

But prosecutors were able to shake Fowler’s credibility. He admitted that in calculating Chauvin’s weight on Floyd’s back, and the detained man’s ability to breathe, he did not take into account the significant weight of equipment worn by the accused former officer.

Fowler’s claims for the part played by carbon monoxide from car exhaust were so unusual that the judge permitted the prosecution to recall one of its key witnesses, Dr Martin Tobin, to rebut the testimony.

The previous week, Tobin held the jury’s attention through technical explanations as to how Floyd was pinned to the ground in a way that caused a lack of oxygen and brain damage.

Recalled to the stand on Thursday, Tobin rubbished Fowler’s calculation that the carbon monoxide saturation in Floyd’s blood was more than 10%, enough to contribute to heart failure. Tobin said tests showed Floyd’s blood oxygen saturation was 98%, leaving just 2% for “everything else”. He said the level of carbon monoxide would have had no impact.

The Irish-born doctor was the final witness in the case. The defense would no doubt have preferred to have had its own specialist wrap up the trial rather than see jurors leave the courtroom having just heard an indictment of his credibility.

But all that Chauvin’s lawyer, Eric Nelson, needs to avoid a conviction on any particular charge is to raise reasonable doubt in the mind of one juror.

That would not be enough to win an acquittal but it might see the accused police officer avoid conviction on the most serious charge of second degree murder and instead found guilty on third degree murder or manslaughter. Or it might lead to a hung jury.

Nelson brought on other experts to help create that doubt. A specialist in the use of force, Barry Brodd, claimed that the way Chauvin pinned Floyd to the ground was “not a use of force”. In any case, he said it was justified for “safety reasons” because if Floyd were to run away while handcuffed he might trip and hurt himself.

Nelson’s unhappiest witness was Shawanda Hill, a friend of Floyd’s who was in his car at the time of the arrest. The defense obliged her to be there in order to demonstrate that Floyd was under the influence of drugs. But it wasn’t clear her testimony helped Chauvin as her recollection of her friend was of a frightened man instinctively scared of the police.