The sister of the 43-year-old New York City father who died after an NYPD officer allegedly used a banned chokehold on him in 2014 left a Manhattan courtroom wailing Monday as the now infamous video of the arrest that led to his death was played.

Eric Garner's mother, Gwen Carr, also left in tears as the video of her son saying "I can't breathe" repeatedly as he gasps for air during that July 2014 confrontation was played on the opening day of officer Daniel Pantaleo's departmental trial. Garner's dying words, captured in widely watched cellphone video, became a rallying cry for a national movement against police brutality.

"These are just tears from heaven," said Carr as rain fell outside the courthouse. "Eric is crying from heaven because he sees his motherand his family still trying to fight for justice for him."

Pantaleo and other officers were trying to handcuff Garner, an unarmed black man, after stopping him on a city street corner for allegedly selling loose, untaxed cigarettes, when Garner started to struggle. He later died. 

The medical examiner ruled Garner's death a homicide caused in part by the cop's apparent chokehold. He was heavyset and had asthma, which were also contributing factors, the medical examiner's office said. 

In opening statements, a prosecutor for the Civilian Complaint Review Board, the police watchdog agency bringing the case against Pantaleo, described the video footage, saying the officer using a "strictly prohibited chokehold."

"Officer Pantaleo buries this helpless man into the pavement, indifferent to his cries for help," the prosecutor said as the video was shown.

The video was played as the man who took it, Ramsey Orta, testified from prison, where he is serving time for drug and weapon charges. During cross-examination, Orta said Pantaleo's arm wasn't around Garner's neck when he uttered, "I can't breathe." 

Orta also backed off a claim he had made to internal affairs investigators two days after Garner's death that Pantaleo had his knee on Garner's back for five to 10 seconds. The video showed it was not on his back. 

Pantaleo's attorney, Stuart London, had argued at a department hearing last month though that the NYPD's chief surgeon ruled in 2014 that the cop hadn't used a chokehold. He re-upped his insistence in opening statements Monday, saying Pantaleo "did not use a chokehold but a neckhold, an approved method ... it's called a seat belt technique. The purpose is to take the individual down."

He also blamed Garner's health for his demise, saying the Staten Island father "died from being morbidly obese ... coupled with chronic asthma. He was a ticking time bomb who set these factors in motion by resisting arrest."

London also used those now infamous words, "I can't breathe," against Garner, saying, "We know he wasn't choked out because he is speaking." He said it was a misconception that those words were said when Pantaleo's hands were around Garner's neck, saying it happened when multiple cops tried to cuff him. 

Emergency medical technicians casually strolled up to the scene without oxygen or other measures that could have helped Garner, who was so medically fragile that even a bear hug might have led to the same consequences, London said.

"The only one that did their job that day, I will submit, is officer Pantaleo," he said, adding Pantaleo feared for his life when he felt Garner was trying to push him toward a plate glass window.

Pantaleo, who is white and has been on desk duty since Garner's death, could face penalties ranging from the loss of vacation days to firing if he's found to have violated department rules. He has consistently denied wrongdoing, and did not speak to reporters as he left his Staten Island home Monday morning.

"Yesterday was Mother's Day," the CCRB prosecutor also said in opening statements. "Nothing will bring Eric Garner back but this court can bring Mr. Garner's family some measure of justice." 

Carr said she wanted just that as she headed into court early Monday, light rain steadily falling across the city. Asked how she was doing, she said briefly, "I feel like the weather." 

"We are looking for justice," Carr added. "We hope the departmental trial proves in our favor." 

Pantaleo does not face criminal charges; a grand jury declined to indict him the year Garner died, prompting days-long protests and marches across the city.

News 4 cameras were rolling when the latest protest unfurled on the FDR at the height of Monday's morning rush. At one point, News 4 saw a van stop in the middle of the southbound lanes; five people jumped out and unfurled a banner. They stretched that sign, which appeared to call for Pantaleo's firing, across the highway, making it impossible for traffic to move by them at the height of Monday's morning rush. NYPD officers responded, but there was no immediate word on possible arrests. Then the protesters started to march toward Houston.

Protesters later also gathered outside police headquarters chanting for Pantaleo to be fired.

The NYPD decided to go forward with the disciplinary case against Pantaleo last year as it ran out of patience with the federal government's indecision about bringing a criminal case. The trial is expected to stretch into June -- and it won't be an easy case for the prosecution. 

A ruling last week requires that the CCRB prove not only that the officer violated NYPD rules, but that his actions fit the criteria for criminal charges.

London says the NYPD shouldn't be handling any prosecution. He took issue with the initial citizen complaint the agency took from someone claiming to be an witness to Garner's death, which became the springboard to the review board's involvement, by questioning the veracity of that account and by extension board's jurisdiction. 

"If I thought this person was actually there, I would not be making this argument," he said outside court late last month. 

Fred Davie, chair of the review board, said the stance was "a baseless attempt to delay officer Pantaleo's prosecution."

He added, "With closure for the Garner family hanging in the balance, the trial for officer Pantaleo must proceed as scheduled and not be further delayed by these meritless maneuvers." 

Garner's family received $5.9 million from the city in 2015 to settle a wrongful death claim. Federal prosecutors have until July to file civil rights charges against Pantaleo.