By Rick Ritter

TOWSON, Md. (WJZ)– The defense rested its case Tuesday in the civil trial of Korryn Gaines, who was killed during an hours-long standoff in 2016 with Baltimore County police in her Randallstown apartment.

Gaines was killed after allegedly pointing a shotgun at officers trying to serve an arrest warrant stemming from a traffic stop that included disorderly conduct and resisting arrest.

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Attorneys for Gaines’ family claim officers used excessive force when they fatally shot her and injured her 5-year-old son. They also say police violated her rights by illegally entering her apartment.

Well-known ballistics expert, Charles Joseph “Joe” Key, was called by the defense to speak Tuesday. He said Officer Royce Ruby’s actions were objectively justified. Key also said Officer Ruby took Gaines’ son, Kodi, into consideration when he initially shot Gaines’ waist, reasonably trying to take a shot that wouldn’t hit Kodi.

The County said “Can a person with mental problems and a shotgun pose as an immediate threat?”

Key answered “Certainly. The only individual who knows why he shot… is Officer Ruby.”

“It’s definitely gonna be a duel. Mr. Key is a wily expert who’s been testifying in courts for the last 40 years,” said J. Wyndal Gordon, attorney for the Gaines family.

On Monday, there was explosive testimony from Officer Ruby that rocked the courtroom. He said he had no choice to fire the first shot because Gaines pointed the shotgun at him.

RELATED: Officer Who Fired Shot That Killed Korryn Gaines: ‘I Had No Choice’

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“Officers will die unless I take that shot,” Ruby said.

“The evidence that we’ve been presenting thus far certainly neutralized, if not, nullified Ruby,” Gordon said.

It’s a decision that will be in the hands of an all-female jury that lost its second juror on Tuesday due to a family emergency.

“We’re still confident that the ones who are remaining were paying attention–they’re taking notes–very attentive. So, we’ll get a fair and just verdict. I have no doubt about that,” Gordon said.

Key is another witness that had major discrepancies between trial testimony and deposition.

County prosecutors previously found Officer Royce Ruby’s shooting legally justified and charges weren’t filed.

Gaines’ family is seeking $4 million.

Closing arguments will be given Wednesday morning.

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Rick Ritter