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Derek Chauvin Trial 4/7/21: Forensic scientist found George Floyd's blood, pills with his DNA in squad car

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Chauvin trial focuses on George Floyd's drug use
Derek Chauvin trial focuses on George Floyd's drug use 02:06

Follow the latest trial updates here. Earlier coverage is below.

A forensic scientist testified in the trial of Derek Chauvin Wednesday that she found George Floyd's blood and pills with Floyd's DNA in the squad car where Floyd struggled with officers. Chauvin, who was seen in disturbing videos kneeling on Floyd's neck for more than nine minutes, is charged with second-degree murder, third-degree murder and second-degree manslaughter.

McKenzie Anderson, a crime scene team leader with the Minnesota Bureau of Criminal Apprehension, testified that she photographed but didn't collect the pills when she first processed the squad car in May 2020. She also found two pills in the car Floyd was driving when she processed it at the same time. She said she re-processed the squad car at the request of the defense team in January 2021 and collected and tested the pills found in the back seat, confirming they contained Floyd's saliva.

Forensic scientist McKenzie Anderson testifies in the trial of Derek Chauvin, April 7, 2021. Court TV/pool via WCCO

Brehana Giles, a chemist with the Minnesota state Bureau of Criminal Apprehension, then took the stand. She said her testing found that the pills in the squad car contained methamphetamine and potential other substances she could not identify. Prosecutors then called Susan Neith, a forensic chemist based in Pennsylvania who also tested the pills. Neith testified she was able to identify fentanyl as well as methamphetamine in the pills found in the squad car, but she said the methamphetamine level was much lower than typical street meth.

Both chemists found that the pills in the car Floyd was driving contained both methamphetamine and fentanyl, and were marked to look like pharmaceutical drugs. Court recessed for the day following their testimony.

The testimony is significant because the defense has suggested that Floyd, who suffered from heart disease, died of a heart arrhythmia brought on by drugs he ingested and adrenaline. The prosecution argues Floyd died of oxygen deprivation beneath the pressure of Chauvin's knee. 

Earlier, LAPD Sergeant Jody Stiger, a prosecution expert in tactics and de-escalation training, testified that Chauvin used deadly force against Floyd. Stiger testified he believed no force was necessary once Floyd was handcuffed, on the ground and no longer resisting.

Stiger testified Tuesday that in his view, officers used excessive force against Floyd during the fatal arrest on May 25, 2020.

"My opinion was the force was excessive," Stiger said.

Stiger told prosecutors he did not believe the crowd of onlookers to pose a threat to officers during the incident, "because they were merely filming, and most of it was their concern for Mr. Floyd." Defense attorney Eric Nelson has attempted to portray the crowd as unruly.

But on cross-examination by Nelson, Stiger acknowledged some of the name-calling and aggressive statements by the crowd could be perceived as a threat.

Chauvin has pleaded not guilty. The other three officers involved are charged with aiding and abetting, and are expected to be tried jointly in August.


Forensic chemist: Methamphetamine levels were low in pills found in cars

Prosecutors called Susan Neith, a forensic chemist based in Pennsylvania who also tested the pills found in the two vehicles, to the stand. Neith testified she was able to detect both methamphetamine and fentanyl in the pills found in the SUV Floyd was driving and in the police squad car.

Neith testified the amount of fentanyl she detected in the pills was about the same as other street fentanyl pills she has tested. But she said the level of methamphetamine was much lower, ranging from 1.9% to 2.9% purity. She said recreational street meth typically is 90-100% purity. 

Court adjourned for the day after Neith's testimony.

By Erin Donaghue

Chemist: Pills with Floyd's DNA contained methamphetamine

Brehana Giles, a chemist with the Minnesota state Bureau of Criminal Apprehension, testified Wednesday she tested the two pills with pharmaceutical markings found in the center console of the vehicle Floyd was driving. When she looked up the markings of the pills, it indicated they contained oxycodone and acetaminophen, but upon testing found they contained methamphetamine and fentanyl. She agreed homemade pills can sometimes be given pharmaceutical markings to make them appear legitimate.

Giles testified she also tested the pills and portions of pills found in the back seat of the squad car, which she found contained methamphetamine. 

On cross-examination from defense attorney Eric Nelson, Giles testified there were indications of other substances in the pills found in the squad car, but she couldn't speak to what they were. 

Giles said she "could not confirm" whether the pills might have also contained fentanyl.  

By Erin Donaghue

Forensic scientist: Pill with George Floyd's DNA found in squad car

Prosecutor Matthew Frank displayed a series of photographs forensic scientist McKenzie Anderson took when initially processing the vehicle George Floyd was driving and the police squad car where the struggle took place in May.

Looking at pictures she took of the inside of the Mercedez-Benz SUV Floyd was driving, Anderson pointed out what appeared to be a pill in the center console. Anderson said she again processed the SUV in December 2020 at the request of prosecutors and collected additional items including pills and the prescription medication Suboxone from the car. Anderson said she collected two pills and two packages of Suboxone, a drug prescribed to help people suffering from opioid addiction.

Anderson then went through a series of photos she took when processing the police squad. She noted what appeared to be a pill on the floor of the vehicle's back seat. Anderson said she didn't collect the item at the time because she didn't know the case involved drugs and wasn't sure if the item had come off of someone's shoe.

"I didn't give it any forensic significance given the information I had," she said.

Later, Anderson said she re-processed the squad car in January 2021 at the request of the defense team and collected the pill, along with several other pieces of what may have been pills that were also in the squad's back seat.

Anderson said she tested one of the pills in the squad car and identified that it had saliva on it that matched Floyd's DNA. 

Anderson also described finding blood in the back seat of the squad car that also matched George Floyd's DNA profile.

By Erin Donaghue

Forensic scientist describes searching vehicles

McKenzie Anderson, a Bureau of Criminal Apprehension crime scene team leader, described responding to the scene of 38th and Chicago, the site of Floyd's fatal arrest. She said she noticed several security cameras in the area, and searched the street near the squad car where officers had earlier struggled with Floyd. 

Forensic scientist McKenzie Anderson testifies in the trial of Derek Chauvin. Court TV/pool via WCCO

She said there was no evidence collected from the scene. She said the squad car and the vehicle Floyd was driving were both towed to the bureau's headquarters to be processed.

She said she processed both vehicles on May 27, 2020 — two days after Floyd's death —along with an agent and another crime scene team member, first by photographing the interior and exterior of the cars, and then by going through items in the car and marking them for collection.

Anderson said she didn't have information at the time that Floyd may have been under the influence of drugs.

By Erin Donaghue

Forensic scientist takes stand

Minnesota Bureau of Criminal Apprehension forensic scientist McKenzie Anderson has taken the stand.

By Erin Donaghue

Agent amends statement; believes Floyd denied doing drugs

Back on the stand after a short break, Reyerson said he had reviewed a longer portion of the body camera video in which he earlier agreed Floyd appeared to say, "I ate too many drugs." Prosecutor Matthew Frank played the longer portion of the bodycam video in court, during which an officer can be heard saying, "I believe so, we found a pipe on him." 

Based on the statements made in the video beforehand, Reyerson amended his earlier testimony, saying he believes Floyd said, "I ain't do no drugs."

By Erin Donaghue

Agent agrees Floyd appeared to say, "I ate too many drugs"

On cross-examination, defense attorney Eric Nelson played a short portion of police body camera video and asked Special Agent James Reyerson whether it appeared Floyd said, "I ate too many drugs." Reyerson said it did. On re-direct questioning by prosecutor Matthew Frank, Reyerson said he had not heard what Floyd might have said beforehand. Floyd's voice in that portion of the video was muffled and hard to understand.

James Reyerson, a senior special agent with the Minnesota Bureau of Criminal Apprehension. Court TV/pool via WCCO

Earlier, Nelson asked whether it's typical and permissible for defense attorneys to ask to review evidence under review by state investigators, and Reyerson agreed it was. Reyerson confirmed that when he said the defense team asked to have the squad car re-processed in January 2021, he was not implying the defense team placed pieces of pills inside the vehicle.

"No sir, I'm not suggesting that," Reyerson said.

Reyerson was also questioned about a trail of liquid on the ground at the scene, and told Nelson it appeared to be condensation from the squad car, rather than Floyd's urine. A firefighter had earlier testified she believed Floyd may have urinated while being restrained.

By Erin Donaghue

More body camera video played in court

Reyerson said the state crime scene team re-processed Floyd's vehicle in December 2020 at the request of prosecutors, and later also re-processed the police squad car at the request of the defense. Defense attorney Eric Nelson has said the defense team discovered pills with Floyd's DNA inside the squad that had not previously been uncovered by investigators. Prosecutor Matthew Frank didn't ask Reyerson what was found inside the vehicle, but indicated another state investigator would testify about re-processing the squad.

Frank then played a portion of the police body camera video showing Chauvin restraining Floyd. Reyerson said it appears Chauvin's left knee was on the back of Floyd's neck, and his right knee was on Floyd's back. 

Frank then played the body camera video alongside the widely-viewed cellphone video filmed by bystander Darnella Frazier, stopping the video in 10-second increments. 

Frank asked Reyerson to identify the moment in the bystander video in which Floyd appeared to stop talking, more than four minutes after he was restrained on the ground, and later, when he stopped moving.

By Erin Donaghue

Special agent details investigation

Reyerson is back on the stand after a lunch break. He has begun to detail his investigation into Floyd's death, describing having Floyd's car and the police squad car towed to the Bureau of Criminal Apprehension headquarters in St. Paul to be processed by a crime scene team. He said he also began collecting and reviewing video evidence.

By Erin Donaghue

Minnesota special agent takes stand

James Reyerson, a senior special agent with the Minnesota Bureau of Criminal Apprehension, has taken the stand. Reyerson is part of a group that investigates police uses of force in the state, and is the case agent for the investigation into Chauvin's actions.

By Erin Donaghue

Expert: Officers had "responsibility to realize something is not right"

Defense attorney Eric Nelson pointed to several body camera images showing the position of Chauvin's knee on Floyd's body. Stiger testified that Chauvin's knee appeared to be in Floyd's neck area, above his shoulder blades. Shown another image taken moments later, Stiger agreed Chauvin's knee appeared to be at the base of Floyd's neck, in between his shoulder blades. Nelson had pursued the same line of questioning with a Minneapolis Police training official on Tuesday, who said Minneapolis officers are trained to place their knee on a person's shoulder while they are prone if they are actively resisting arrest.

On re-direct questioning by prosecutor Steve Schleicher, Stiger said the risk of a person suffering breathing complications while prone would be increased by pressure anywhere on their body.

Stiger testified the officers had a duty to help Floyd when it became clear "his health was deteriorating," as his movements and breathing were slowing.

"As an officer on the scene, you have a responsibility to realize something is not right, something has changed drastically than what was occurring earlier, so therefore you have a responsibility to take some kind of action," Stiger said.

By Erin Donaghue

Defense again hones in on crowd's behavior

Stiger agreed with Nelson that there are circumstances when a person who had once resisted arrest and then complied with officers could become combative again. But Stiger qualified his answer by saying use-of-force should be dependent on the suspect's actions at the time, not what they may do in the future.

Nelson again focused on the behavior of the crowd of bystanders, which Stiger had earlier said did not appear to pose a threat to officers. Nelson asked Stiger whether the crowd grew more excited over time.

"More concerned, I would phrase it," Stiger responded.

Nelson pointed to training that Chauvin had received in March of 2020, several months before the fatal arrest, about dealing with large crowds. Nelson read from a portion of the training that portrays crowd behavior as dynamic and warns officers to "never underestimate a crowd's potential."

Stiger agreed a reasonable officer could perceive name-calling by a crowd as a safety risk.

"A risk, possibly, but officers are typically trained when it comes to verbal threats in and of themselves, they can't use that to justify force," Stiger said.

Nelson asked whether using a series of expletives and the phrase, "I'm going to slap the f--- out of you" could be perceived as a threat. Stiger agreed it could.

By Erin Donaghue

Defense cross-examines training expert

Under cross-examination by defense attorney Eric Nelson, Stiger agreed that any analysis of whether an officer's use of force was reasonable should include the totality of the circumstances of the incident. Stiger agreed that Chauvin would have been in a heightened state of awareness after receiving a call from dispatchers to respond to the scene where a suspect who was 6 or 6-and-a-half feet tall, and possibly under the influence, was resisting arrest.

Nelson pointed out that Floyd said "I can't breathe" as officers were attempting to put him in the squad car, before he was restrained. He asked Stiger whether he has known suspects to feign a medical emergency such as a heart attack in order to avoid arrest. Stiger said he had.

Stiger agreed that handcuffed suspects can still kick or thrash. When asked whether "the notion that a handcuffed suspect no longer presents a threat to an officer is not correct," Stiger replied, "It depends on the circumstances."

Nelson played a clip of a body camera video showing a restrained Floyd and asked whether it sounded as if Floyd said, "I ate too many drugs." Stiger said he couldn't make out what Floyd was saying.

Stiger agreed when Nelson said there are circumstances when a use-of-force incident recorded on a video "looks bad, but it's still lawful."

Use-of-force expert testifies Derek Chauvin should have used "no force" 23:02
By Erin Donaghue

Expert: Crowd of onlookers did not pose threat

Stiger testified he did not perceive the crowd of onlookers during Floyd's arrest to be a threat, though he said there was some name calling and foul language directed towards the officers. When asked why the crowd did not seem threatening, Stiger said, "Because they were merely filming, and most of it was their concern for Mr. Floyd."

Stiger said crowds can be distracting, but said he did not believe the crowd in this case distracted Chauvin from being attentive to Floyd because Chauvin was responding to Floyd's expressions of pain. Prosecutor Steve Schleicher played a portion of body-worn camera in which Chauvin is heard telling Floyd, "It takes a heck of a lot of oxygen to talk."

Defense attorney Eric Nelson has portrayed the crowd of onlookers as unruly and suggested the group may have posed a threat to officers. 

On cross-examination by Nelson, Stiger said he had not received training from the Minneapolis police department, but has reviewed their policy. He also acknowledged not all of the thousands of use-of-force cases he's reviewed in his career involved deadly force.

By Erin Donaghue

Expert: "No force should have been used" after Floyd was handcuffed, not resisting

Under questioning from prosecutor Steve Schleicher, Stiger described the position of Chauvin's knee on Floyd's body in a series of still images taken from an officer's body-worn camera. Stiger testified Chauvin's left knee was on Floyd's neck and his right knee was on Floyd's back, and that the positioning of his knee did not change throughout the nine minutes and 29 seconds Floyd was restrained.

On Tuesday, defense attorney Eric Nelson had pointed to body camera images during the testimony of a Minneapolis police training official, who said Chauvin's knee appeared to be between Floyd's shoulder blades.

Stiger pointed out an image in which he said Chauvin appeared to be using a "pain compliance" technique on Floyd's hand.

Stiger also testified that Floyd did not pose an immediate threat to officers while he was restrained.

"He was in the prone position, he was handcuffed, he was not attempting to resist, not attempting to assault officers, kick or punch or anything of that nature," Stiger said.

Floyd did not verbally threaten officers or communicate that he would attempt to resist them, Stiger said.

When asked by Schleicher how much force would be reasonable to use against Floyd after he was handcuffed, prone and not resisting, Stiger said, "My opinion was that no force should have been used once he was in that position."

Stiger said Chauvin's force against Floyd was deadly because of the well-known risks of positional asphyxia or breathing complications.

By Erin Donaghue

Court resumes with training expert's testimony

LAPD Sergeant Jody Stiger is back on the stand, continuing his testimony as a training and use-of-force expert for the prosecution.

By Erin Donaghue

Floyd's last words "agonizing," brother says

George Floyd's brother Rodney Floyd sat Tuesday in the lone seat in the courtroom reserved for members of the Floyd family. 

"It's nail-biting, it's like watching a movie," Rodney Floyd said. "There's so many ideas of what's gonna happen."

He told a pool reporter the last time he was inside the courtroom was last week, when prosecutors played a series of police body camera videos. The videos showed the fatal encounter close up, with Floyd's pleas for air clearly audible. 

"That was very, very hard," Rodney Floyd said. "I don't know where I grabbed the strength because it was back and forth like it was never gonna end."

Rodney Floyd, brother of George Floyd, enters the heavily secured Hennepin County Government Center Tuesday, April 6, 2021, in Minneapolis where testimony continues in the trial of former Minneapolis police officer Derek Chauvin. Chauvin is charged with murder in the death of George Floyd during an arrest last May. Mark Vancleave/Star Tribune via AP

He told the reporter his brother's dying words from the video were displacing his memory of the last conversation they had together, during which they reminisced about their late mother. Rodney Floyd said it made sense to him that his brother called out for their late mother, because "he said mom was heavy on his mind. He's a momma's baby."

"When someone dies, you cherish their last words, but my brother's last words, oh, those words are stuck in my head," he said. "Agonizing."

By Erin Donaghue

Recap of police chief's testimony

Minneapolis Police Chief Medaria Arradondo testified on Monday that Chauvin's actions violated Minneapolis police policy.

Arradondo said there was an "initial reasonableness in trying to just get [Floyd] under control" in the first few seconds of the May 25 encounter. But when Floyd had stopped resisting, and "clearly when Mr. Floyd was no longer responsive and even motionless, to continue to apply that level of force to a person prone out, hands cuffed behind their back — that in no way, shape or form is anything that is by policy," Arradondo said. "It's not part of our training and it's certainly not part of our ethics or values."   

Police chief testifies Derek Chauvin's actions violated policy, training 03:21
By Erin Donaghue

Floyd's cause of death a key point of dispute

A key point of dispute in the trial has been how Floyd died. During opening statements last week, prosecutors played the video of Floyd being pinned down, saying Chauvin used lethal force against a "defenseless" and handcuffed Floyd for nine minutes and 29 seconds. Prosecutor Jerry Blackwell said Floyd died of oxygen deprivation beneath the pressure of Chauvin's knee. But the defense argued Floyd, who suffered from heart disease, died of a heart arrhythmia complicated by the fentanyl and methamphetamine he ingested before his arrest.

Doctor testifies about George Floyd's cause of death 09:27

Monday, Dr. Bradford Langenfeld, the emergency doctor who tried to resuscitate Floyd and ultimately pronounced him dead, testified that paramedics did not tell him that Floyd suffered a drug overdose or a heart attack. When asked by Blackwell whether he believed oxygen deficiency was the cause of Floyd's death, he responded it was "one of the more likely possibilities."

Langenfeld agreed a more common term for the possible cause of death would be asphyxia. 

Under questioning from defense attorney Eric Nelson, Langenfeld agreed that drug use, including from methamphetamine and fentanyl, can cause a lack of oxygen to the brain. Langenfeld agreed that Floyd had "exceptionally high" levels of carbon dioxide in his system, which he agreed can result from fentanyl use. Langenfeld testified that heightened levels of carbon dioxide can affect the respiratory system and cause a feeling of shortness of breath.

Later, on re-direct questioning from Blackwell, Langenfeld said he considered the elevated carbon dioxide level to be "weak evidence" in relation to Floyd's cause of death, because it indicates someone's heart has stopped but no indication as to why.  

By Erin Donaghue

The charges

In order to convict Chauvin of second-degree murder, prosecutors will need to prove beyond a reasonable doubt that Chauvin caused Floyd's death while committing or attempting to commit a related felony, in this case third-degree assault. To convict the former officer of third-degree murder, prosecutors must convince the jury that Chauvin caused Floyd's death during an act that was "eminently dangerous to others and evincing a depraved mind, without regard for human life." 

In this image from video, defense attorney Eric Nelson, left, and fired Minneapolis police officer Derek Chauvin listen during Chauvin's murder trial at the Hennepin County Courthouse in Minneapolis. Chauvin is charged in the May 25, 2020, fatal arrest of George Floyd.  Court TV via AP, Pool

The third-degree charge was initially dropped by Judge Cahill, but was re-instated earlier this month after an appeals court handed a win to prosecutors.

To convict Chauvin of second-degree manslaughter, prosecutors will need to prove beyond a reasonable doubt that Chauvin caused Floyd's death by "culpable negligence," meaning he created unreasonable risk and consciously took a chance of causing death or serious harm.

Prosecutors do not need to prove that Chauvin intended to cause Floyd's death. Since police officers are authorized to use force, prosecutors must prove that the force Chauvin used against Floyd was unlawful.

In Minnesota, second-degree murder carries a maximum sentence of 40 years in prison. Third-degree murder is punishable by up to 25 years. Second-degree manslaughter carries a maximum prison term of 10 years.

By Erin Donaghue
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