Welcome to the Lead M. Jake Tapper. You've been watching some of the most anticipated testimony in the murder trial of former Minneapolis police officer Derek Chauvin.

The man who performed the autopsy on George Floyd is testifying Hennepin County Chief Medical Examiner.

Dr. Andrew Baker, he ruled Floyd's death a homicide when he performed the autopsy in May 2020.

Though his Dr. Baker just explained homicide means something different to a medical examiner than it does to a prosecutor, to a medical examiner.

It essentially means that the death was caused by the actions of another person.

It's not an assignment of guilt or malicious intent necessarily.

Dr. Baker said the primary cause of death was the restraint by law enforcement.

Though he said Floyd's health conditions and the drugs in his system did play a role.

Let's continue to listen in.

Sometimes a little fashion sign wrong. We're going to take a 15 minute break.

All right, so they are taking a 15 minute break and while they do that, let's go over what we have learned today.

CNN's Omar Jimenez is in Minneapolis covering the trial for us.

Omar walk us through the medical examiner's testimony today.

It was very highly anticipated.

What do you or the big headlines?

Yeah, Jake, very highly anticipated because really the crux of the defense's argument comes down to what the actual cause of death is.

During cross examination, he said in court, the chief medical examiner, I believe heart disease and drugs played a role in George Floyd's death.

As we went further on into testimony and prosecutors were able to do a redirect examination, question him again.

He clarified saying that he believes those were contributing factors, not necessarily the actual causes.

But then another point in this is comes down to the actual amount of drugs that was in George Floyd's system.

We knew that there were amounts of fentanyl.

We knew that there were amounts of methamphetamine.

...