She tearfully identified a photo of her late husband, Officer Andrés Vásquez Lasso, and recalled seeing him for the last time at the hospital.
Jurors also heard from the then-girlfriend of Steven Montano. She called 911 when they were arguing, and says Montano rushed her and told her he had a gun.
Under cross-examination, Linda Parea acknowledged she never saw his gun, and she did not fear for his life.
Emotions ran deep, as the jury saw the first body camera of the deadly shooting.
Wife of slain CPD officer 1st to testify in accused murderer's trial
It showed Montano being arrested. He was bloody, as he was shot in the chin.
Some of the video is too graphic to show.
A crossing guard who saw a man and woman arguing the day of the shooting also testified. The jurors were shown video surveillance of the block.
Other police officers who responded to the scene testified, and jurors heard from neighbors who said they saw Montano running away and jumping a fence with a gun.
The day began with opening statements in the trial against the man accused of killing Chicago police Officer Vásquez Lasso.
Prosecutor Katy Siefert told jurors, "The defendant fired at a uniformed officer not once, not twice. He fired at Officer Vásquez Lasso five times."
Defense attorney Hussain Khan told jurors Montano was only 18 at the time, estranged from his family and under the control of an older woman, describing the shooting as an "unfortunate reaction," saying "he was deescalating. He was running away."
Dozens of Chicago police officers were in court for a show of support for Vásquez Lasso. Multiple family members of the fallen officer were also in court as the trial got underway .
Carlos Yañez Jr., a CPD officer who was seriously injured in a shooting that killed his partner, Officer Ella French, was also present.
"I know how difficult, important (it is) to show support," Yañez said.
Tuesday morning, a judge swore in the jury and gave them instructions. There are 12 jurors and four alternates.
Steven Montano is charged with first-degree murder in Vásquez Lasso's death.
It was in March 2023, when Officer Vásquez Lasso was responding to a domestic call near 52nd Street and Spaulding Avenue in Gage Park.
PREVIOUS COVERAGE | Chicago police officer Andres Vasquez-Lasso shot, killed in Gage Park; suspect charged with murder
The call was about a man with a gun chasing a woman down the street.
Officer Vásquez Lasso was shot during a shootout with the suspect, following a chase.
"It's sad that Andrés lost his life trying to defend a female who was in fear of hers; our officers do this every day, sometimes multiple times a day," local Fraternal Order of Police President John Catanzara said.
Montano is also facing two gun-related felonies and misdemeanor counts of interfering with a report of domestic violence.
Officer Vásquez Lasso was with the Chicago Police Department for five years. He was 32 years old and married at the time of his death.
Among the group of people showing their support for the family of the fallen officer were members of the Teamsters Union.
"Right now, this is personal. This is family here. So, we're to support the fallen officer and the family," said Ramon Williams, president of Teamsters Local 700.
"Public sector employees have a bond; we want them to know that we are a brotherhood, and we're here to support them, as well," Teamsters Local 700 Vice President Anthony McGee said.
Members of Montano's family were also in court.
The trial is expected to last a week. It resumes Wednesday at 10 a.m. at the Leighton Criminal Courthouse.