D.C. Mayor Muriel E. Bowser used a news conference last week to urge residents to help police find the man accused of shooting at a Metrobus and wounding a passenger.

But there was another reason she focused on the suspect, Bijon Lamont Brown. The 20-year-old, according to police, is among the convicted gun offenders who are fueling a wave of summer violence.

“We want to especially follow what his experience has been in the criminal justice system,” Bowser (D) said.

Just two months ago, Brown admitted to shooting a youth in the legs in a February attack on a basketball court in Southeast Washington and tossing the gun into the Anacostia River. As part of a deal with prosecutors, the only time he spent behind bars was the four months between his arrest in March and his sentence in July.

D.C. Police Chief Cathy L. Lanier said a law enforcement task force formed in 2007 now plans to track gun offenders such as Brown — through arrest, trial, sentencing and release — to determine how so many are returning so quickly to the streets after their crimes.

Bijon Brown (Courtesy of Metro Transit Police)

Court records in Brown’s earlier case show the complexity of such sentencing decisions, with a more nuanced look at what may appear to be a lenient deal. Lawyers on both sides noted that he pleaded guilty after making a quick and remorseful confession. He grew up in one of the District’s most violent neighborhoods. He had no prior convictions as an adult. He had been attacked before. And the youth he shot refused to cooperate with authorities.

The U.S. attorney’s office did not oppose Brown’s bid for one year of probation, and a prosecutor agreed the defendant had “made significant progress toward rejoining the community.”

But less than one month after the plea, Brown found himself back in the cross hairs of police — charged in the Aug. 21 shooting on the bus. Police said they believe he was shooting at someone, and a bystander was struck.

That Friday night shooting came amid a surge in violence that police have attributed partly to more guns on the street and to repeat offenders. Lanier said that more than half of the people arrested so far in this year’s homicides had prior gun arrests in the District, helping drive a 47 percent increase in killings in 2015.

On the last weekend in August alone, police arrested 24 people in connection with 34 gun seizures. Lanier said that 14 of those suspects had been arrested on gun charges in the past, several more than once, in connection with robberies, burglaries and carjackings.

“These are the folks that are driving a lot of the crime in the District,” Bowser said, calling for a review “to hold all of our partners accountable.”

Bill Miller, a spokesman for the U.S. attorney’s office, said the plea agreement with Brown “was made after a comprehensive review of the evidence.”

“The case presented significant legal challenges, including police investigative work, that made this plea the best possible outcome, given the circumstances,” Miller said. He added that prosecutors considered Brown’s quick acceptance of responsibility, his lack of a prior adult record and the lack of cooperation from the victim, among other factors.

Delroy Burton, chairman of the D.C. police union, questioned the mayor for holding Brown up as an example for the District’s rise in violent crime.

“I think the prosecutors believed from the defendant’s actions that the arrest scared him enough,” Burton said. Noting the charges a month later in the bus shooting, he said: “They appear to have been proven wrong. But it doesn’t mean we shouldn’t try to save these people.”

Burton has been critical of the police chief’s crime strategy, arguing that her deployment and management decisions have contributed to the problem more so than additional guns or repeat offenders. He said that Lanier and Bowser “still have not shown why this is responsible for the surge in violence. . . . How are we supposed to trust them that these few reasons are why things are the way they are in D.C.?” He called for the council to enact mandatory minimum prison sentences for gun offenders, to give those convicted “a certainty of punishment.”

Brown admitted to shooting the youth on the basketball court in the 2500 block of Pomeroy Road SE, in Barry Farm, on Feb. 16. Police initially said he shot two people, but court documents show that he fired on two brothers and struck one as they walked from their apartment to a corner store. Brown said he fired four or five shots but did not mean to hit anyone, according to court papers.

A police arrest affidavit shows that detectives at first focused on a different man who fit Brown’s description, but witnesses pointed police toward Brown after seeing surveillance video. Police arrested Brown in March after he voluntarily came to the station to be interviewed. His attorney, Geralyn R. Lawrence, wrote in court documents that Brown acknowledged the shooting “was a terrible decision” and he “expressed remorse continuously during the police interview.”

Lawrence wrote that Brown grew up amid violence in his troubled neighborhood and had been “the victim of a series of attacks by a large number of individuals who repeatedly attacked him with and without weapons on repeated occasions.”

Once, she wrote, Brown was stabbed in the back and chest “when he was not able to outrun his assailants.” Lawrence said Brown was attacked again hours before he shot at the youths on the court. Brown has a juvenile record, court documents say, but no details were provided. His conviction in the basketball court shooting was his first as an adult.

The defense attorney urged the court to “consider all the unique circumstances” that led to “his poor choice” in opening fire, and she said her client “never tried to minimize his responsibility or use such as an excuse for his conduct.” Brown enrolled in a summer program at Ballou High School — he had a 3.3 GPA in his previous high school — and planned to pursue a degree in mortuary science. Lawrence did not return repeated calls seeking comment. Neither Brown nor his relatives could be reached.

Lawrence said in court documents that the shooting, while “a serious crime,” also “reveals an immaturity and lack of criminal sophistication of an offender who minimizes the hardships and poverty he faced growing up under difficult circumstances.”

“Mr. Brown is still a young man making the difficult transition to self-sustaining adulthood,” the attorney wrote. She urged probation as “a sentence designed to correct his behavior.”

Prosecutors agreed. Assistant U.S. Attorney Scott E.Ray wrote in court papers that Brown’s willingness to plead guilty “saved the people of the District of Columbia valuable time and resources” in sparing a trial, and that the government “gives credit to the defendant for accepting responsibility early in these proceedings.”

Scott also noted that Brown “offered an explanation of why he felt the need to use a firearm and expressed regret for making that decision.”

As of Sunday, authorities said Brown was still at large.

Lynh Bui contributed to this report.