Jurors who heard the biggest gang trial in recent Chicago history on Wednesday convicted the core leadership of the Hobos, a group described by prosecutors as an “all-star team” of criminals whose ruthlessness contributed to the city’s alarming spike in homicides.

To extend their power on the South Side, prosecutors said, the Hobos cultivated a reputation for brutality so terrifying to witnesses that some chose to go to jail rather than provide evidence against gang leaders.

The conspiracy allegedly included the murders of at least nine people, including gang rivals and government witnesses. One victim was fatally shot in 2013 in front of his screaming stepchildren to stop him from testifying. Another incident involved the robbery of NBA player Bobby Simmons at gunpoint outside a nightclub for a $200,000 diamond-and-gold chain.

Jurors deliberated for six days before returning the verdicts against accused Hobos boss Gregory “Bowlegs” Chester, alleged hitman Paris Poe and four others. They were convicted of racketeering conspiracy and drug and weapons charges.

So feared are the Hobos that some witnesses were visibly nervous as they took the stand with alleged gang leaders looking on. One refused outright to speak against the gang, telling the judge, “I choose not to testify for the sake of me and my family.” The witness was held in contempt and given a 60-day sentence.

The convictions followed a bloody year on the streets of Chicago. The nation’s third-largest city logged 762 homicides in 2016, the highest tally in 20 years and more than the combined total of the two largest cities New York and Los Angeles. More than 50 people were shot and 11 killed over the long Christmas weekend alone as some gangs sought out and shot rivals at holiday parties, police said.

There are more than 150,000 street-gang members in Chicago, though many are not active, according to the Chicago Crime Commission, a non-governmental group that advocates for law enforcement. The Hobos trial was considered significant because so many purported gang leaders were on trial simultaneously and because of how prosecutors portrayed the group as uniquely vicious.

Prosecutors have said for years that dismantling gangs is a key to reducing violence in Chicago. They used racketeering laws to convict other gang bosses, including Latin Kings leader Augustin Zambrano in 2011. The laws enable prosecutors to go after individuals, not necessarily for specific crimes but for their leadership of groups that displayed patterns of illicit activity over years.

Experts said an underlying cause of gang violence was the demolition of public housing starting in the 1990s that dispersed gang members into rival-gang neighborhoods. Others pointed to an unintended consequence of prosecuting gang leaders: breaking up a gang’s command structure leads to inter-gang rivalry that generates even more violence.

Others say causes of violence are more varied, pointing to poverty and growing availability of high-caliber guns. And even when gang members are involved, deadly conflicts sometimes arise from insults or perceived slights rather than territorial disputes, gang expert John Hagedorn has argued.

The Hobos had fewer members than the Latin Kings, Vice Lords and other gangs. But they were well-organized, well-armed and quick to kill. Hits were often carried out in daylight, including one five-car drive-by shooting that killed two Black Disciple rivals outside a funeral home. Hours later, the Hobos celebrated the killings at a luxury hotel off Michigan Avenue, prosecutors said.

Poe killed a government witness named Keith Daniels, who was a gang associate-turned-informant, days after Chester’s arrest and after Daniels testified to a grand jury in the racketeering case, prosecutors said. He stood over Daniels and shot him more than a dozen times at close range as the man’s four-year-old stepdaughter and six-year-old stepson looked on.

In a courtroom video, the boy recalled shots coming through the windows before his stepfather stumbled from the family car, saying, “I was covering my ears because the gunshots were too loud.”

The onus was on prosecutors to prove not only that the six men committed crimes, but that they coordinated their crimes.

Chester, 39, was the only defendant to testify, insisting the Hobos gang did not even exist despite his full-arm tattoo emblazoned with the words: “Hobo: The Earth is Our Turf.” And he said the supposed “Hobos horns” gang sign he flashed in photographs was merely a universal sign of celebration.

Born with badly deformed legs, Chester scoffed when asked if someone who struggled to even walk could head a gang. “A crippled gang leader?” he answered. “No, sir.”

Prosecutor Timothy Storino told jurors Chester led “not with his legs but with his head”, calling him “smart as hell”. Chester relied on others, sometimes children, to do the dirty work, authorities said.

Chester said he grew up poor in the now-demolished Robert Taylor projects where “only the strong survived” and faced ridicule because of his deformities.

He described himself as a “hustler” who dealt heroin, then smartly invested in record labels and clubs. He said the other five charged had nothing to do with his crimes and he had nothing to do with theirs.

Defense lawyer Beau Brindley told jurors that authorities manipulated evidence against Chester, likening the investigation to an archer who shoots an arrow and then draws a target around wherever it lands.

Sentencing of the six was set for June 23.