Police officers smelled marijuana coming from the open window of the silver Cadillac they pulled over Sunday night. The 19-year-old in the back seat, they said, refused to get out of the car or show his hands.

Officer Andrew Groman, who is white, pointed his stun gun and threatened to shoot, police said. The young man, who is black, pulled a .357 Magnum revolver and fired — the bullet pierced the officer’s stomach and seriously wounding the 27-year-old.

Police and the suspect’s attorney say that the split-second decisions by each man that night were shaped by the deaths of unarmed men at the hands of police in Ferguson, Mo., and New York. It was a moment that shows how those deaths — and the outrage that followed — have begun to change policing and the public’s interactions with officers.

Police and union officials worry that Groman — and other officers across the country — are now too hesitant to pull their weapons. The attorney for Donte Jones, the alleged shooter, said his client’s “survival instincts” kicked in and, facing a police officer, he “came to the conclusion that his life was on the line.”

Both the Baltimore police union and Jones’s attorney dispute the other’s claim to fear, but they agree that the dynamic between police and the community has changed, seemingly overnight. The city is another left struggling to comprehend an instant flash of gunfire and its broader repercussions.

Donte Jones (Photo by Baltimore Police Department)

“Police have a rough job . . . and we got bad guys on the street who carry guns who would hurt anybody,” said Tessa Hill-Aston, president of the Baltimore branch of the NAACP. But the events around the country have put many citizens on edge, worrying that “police are going to jump or pull a gun because they’re nervous.”

The sentiment in Baltimore has echoed in urban areas and small towns, said Chuck Wexler, director of the Police Executive Research Forum, a law enforcement think tank.

Wexler called Ferguson a defining moment that is in the back of every police officer’s mind every time that person stops somebody. “This kind of scrutiny has made everybody step back and carefully examine every action taken as to whether it’s appropriate and defensible,” he said.

D.C. Police Chief Cathy L. Lanier, speaking last week with NewsChannel 8’s Bruce DePuyt, said she had mingled with the marchers who have protested the killings by police of Michael Brown in Ferguson and Eric Garner in New York and viewed their grievances broadly.

“It’s not a ‘I hate the police’ movement,” she said.

Rather, the chief said it’s about the justice system and about “how do we police poor communities, and how do we police wealthy communities.” But Lanier also said that the constant drone of criticism “is hard on all of us.”

Delroy Burton, chairman of the D.C. police union, said he has worried for weeks that “all the negative rhetoric is going to get some unhinged person to think they can take some crazy action against a police officer. And here we are.”

Bishop D. Demond Robinson and 25 residents of Ferguson took an 800-mile road trip from Missouri to Washington to march with other protesters from around the country in opposition of police brutality. (Whitney Leaming/The Washington Post)

Burton said that “officers are people, and they understand the politics at play. They see all the second-guessing that is going on. They don’t want to be second-guessed, so they hesitate. You hesitate, you could lose your life.”

While police argue that officers need to act on training so they can react instinctively in tense moments, that doesn’t mean that they can’t make better decisions, said Cortly “C.D.” Witherspoon, a leading Baltimore activist who heads the city’s chapter of the Southern Christian Leadership Conference.

“We want them to be thinking men and women, to have a pulse, and a heart and a conscience,” Witherspoon said. ‘We want them to have compassion for human life.”

Warren A. Brown, a prominent Baltimore defense lawyer who once ran unsuccessfully for the city’s top prosecutor job, represents Jones. He said his client and others reasonably fear for their safety when they encounter police.

“In the hood, so to speak, people are always concerned about the police and the thugs,” Brown said. “Good people get caught between the two.”

Sunday night’s shooting near a shopping mall in West Baltimore came after protesters wound through parts of the city, an extension of daily marches shutting streets and intersections. They shouted the mantra from Ferguson, where police officer Darren Wilson fatally shot Brown, an unarmed 18-year-old: “Hands up, don’t shoot.”

Baltimore wasted no time framing the shooting there against a volatile political backdrop. At the crime scene Sunday night, the city’s black police commissioner, Anthony W. Batts, articulated the frustrations of his officers: “We’ve had marches nationwide over the fact that we have lost lives in police custody. I wonder if we’ll have these same marches as officers are shot, too.”

Whether to motivate his 2,800 officers or to challenge the protesters, Batts said precisely what others had taken pains to avoid: assigning a moral equivalency to assaults on police and assaults by police. The mayor quickly tried to smooth over words after protest leaders demanded an apology, telling the Baltimore Sun, “The danger in mixing them is you lose the importance of both those issues.”

Mayor Stephanie Rawlings-Blake (D) told reporters she was worried, saying she had heard that officers in her city and others “feel at greater risk.”

Lt. Gene Ryan, president of the Baltimore police union, said officers are telling him that they’re being tentative. “They aren’t afraid of getting in trouble at work; they’re afraid of going to jail. When you have a split second to react, that’s a recipe for disaster.”

Ryan, a 32-year veteran, said he would have had his gun out on Jones. He called Warren Brown’s assertions absurd and said Jones was trying to escape jail, not death. “The less support officers get, the more afraid they’re going to be to take actions that are appropriate, and to save their lives or someone else’s.”

Groman remains hospitalized and has made no public statements. His family has not responded to interview requests. He grew up in Warrington Township, Pa., north of Philadelphia, and worked for the volunteer fire department, like his father and grandfather. He rose to the rank of captain, and though he moved to Baltimore when he joined the police force three years ago, he still returns home to help out with fires.

“He seemed very content with what he was doing,” said the township’s fire chief, Michael Bean. “He is a great public servant. He just genuinely cares.”

Brandon Scott, a Baltimore city councilman who is vice chairman of the public safety committee, said the city is a safer place than the Baltimore he grew up in during the record-setting murderous years of the 1990s. But he worries about the growing divide between residents and officers.

“Citizens can’t treat every cop as if they are Darren Wilson,” he said. “And police can’t treat every black man as Public Enemy Number One.”