The jury in the trial of Derek Chauvin, the ex-Minneapolis policeman accused of killing George Floyd last year, has retired to consider its verdict.

The prosecution told jurors that Mr Chauvin had murdered Mr Floyd, but the defence said their client had correctly followed police training.

The court is being protected by barbed wire, high barriers and armed soldiers from the National Guard.

Cities across the country are bracing for protests regardless of the verdict.

Mr Chauvin's lawyer Eric Nelson argued that his client did what any "reasonable police officer" would have done after finding himself in a "dynamic" and "fluid" situation involving a large man scuffling with three officers.

He said Mr Chauvin's body camera and badge were knocked off his chest owing to "the intensity of the struggle".

Mr Nelson also argued that Mr Floyd's drug use was "significant" because the body reacts to opioid use, specifically in the case of someone who had been diagnosed with hypertension and high blood pressure.

The lawyer also argued that his client was unlikely to have intentionally violated use-of-force rules as he would have been aware that the whole interaction was being recorded. "Officers know that they are being videotaped," added Mr Nelson.

Prosecutor Steve Schleicher urged jurors to "use your common sense. Believe your eyes. What you saw, you saw," referring to the video showing Mr Chauvin kneeling on Mr Floyd for more than nine minutes last 25 May.

"This wasn't policing; this was murder," he added.

Prosecutor Jerry Blackwell had the final word on Monday. He said the matter was "so simple that a child can understand it".

"In fact, a child did understand it, when the nine-year-old girl said, 'Get off of him,'" Mr Blackwell said, referring to a young onlooker who objected. "That's how simple it was. 'Get off of him.' Common sense."

What happens now?

The jury will be sequestered to consider testimony from 45 witnesses, including doctors, use-of-force experts, police officers, bystanders and people who were close to Mr Floyd.

The defendant is charged with second-degree unintentional murder, third-degree murder and manslaughter. Mr Chauvin faces up to 40 years in prison if convicted of the most serious charge - second-degree murder.

A conviction on any of the counts against him will require the jury to return a unanimous verdict. A single juror holding out would result in a mistrial, but the state could then try Mr Chauvin again.

Of the 12 jurors, six are white, four are black and two are multiracial. Seven are women and five are men.

How is the US preparing for the verdict?

The footage of Mr Chauvin, who is white, restraining Mr Floyd, a black man, on the floor as he shouted "I can't breathe" spurred months of global protests in 2020.

On Monday the governor of Minnesota, Tim Walz, requested security assistance from the states of Ohio and Nebraska ahead of the verdict.

The Democrat was heavily criticised after more than 1,000 buildings and businesses were damaged in rioting last year.

In the early hours of Sunday, two National Guard members who were providing neighbourhood security in Minneapolis escaped with minor injuries when they were shot at in a drive-by shooting. (BBC)

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