Glenn Chin prepared epidural steroid injections, for patients with back pain, in conditions he knew were filthy and unsafe, federal prosecutors told jurors Tuesday, a deliberate oversight that led to a 2012 meningitis outbreak that killed dozens and sickened hundreds.

Assistant US Attorney George Varghese said Chin, the former supervisory pharmacist at the New England Compounding Center, is responsible for the deaths of 25 people, including Edward Lovelace, a Kentucky judge who suffered a massive stroke after he was injected with medication from the Framingham lab.

“Judge Eddie was killed by that man,’’ Varghese said during his opening statement in Chin’s trial for second-degree murder. “He knew there was a reasonable likelihood someone would die, and somebody did.’’

The fungal outbreak was blamed for 64 deaths and hundreds of illnesses. In 2014, a dozen people were indicted in connection with the scandal, including six pharmacists. Chin and Barry Cadden, the center’s head pharmacist, were charged with second-degree murder in the deaths of 25 people who received injections that were tainted with mold.

Prosecutors say Chin and Cadden used expired medication, mislabeled drugs, and distributed drugs they knew could be tainted with fungus. In March, Cadden was convicted of conspiracy, mail fraud, and racketeering but was acquitted of second-degree murder. He was sentenced to nine years in prison.

On Tuesday, defense lawyers said Chin, 49, was not responsible for the deaths. They instead blamed Cadden, whom they described as a cruel and demanding boss eager to push out more pharmaceuticals to increase profits.

“Glenn Chin couldn’t say no to him. Nobody told Barry Cadden what to do,’’ Stephen Weymouth, one of Chin’s lawyers, told jurors during his opening statement. “Glenn Chin was not anything other than an employee.’’ Chin was a salaried employee who did not get a commission and did not stand to gain financially by pushing production over safety, Weymouth said.

But Varghese told jurors Chin had reason to believe his actions could have fatal consequences.

“His intention was to make money. . . . His actions demonstrated a shocking disregard for human life.’’

Varghese showed jurors photographs of the 25 people who died in 2012, describing them as “murder victims.’’

“All 25 lives lost because of Mr. Chin, because of his extraordinarily dangerous conduct, because of his complete disregard for human life,’’ Varghese said.

Chin handled the production of more than 17,000 vials of the epidural steroid that were later found to be contaminated with fungus, prosecutors said. But Weymouth said there is no evidence to show it was Chin who contaminated the vials or that he knew they were compromised when they were sent out.

When the vials were prepared, the medication was tested and found to be sterile, Weymouth said. The contamination occurred after they were placed on a quarantine shelf in the lab.

“Nobody knows exactly what happened,’’ Weymouth said. “You’ll never hear anyone tell you, ‘This is how the product got contaminated.’ ’’

During the jury’s lunch break, Chin’s lawyers angrily moved for a mistrial on the grounds that Varghese had incorrectly defined second-degree murder and made other misleading statements to the jury.

US District Judge Richard Stearns denied their request but explained to jurors the mistakes in Varghese’s statement.

During his opening, Weymouth was visibly angry at Varghese, derisively referring to him as “this prosecutor’’ and dismissing parts of his statement as “balderdash.’’

“There were things this prosecutor told you that are not going to be supported by the evidence,’’ Weymouth said. “They’re not going to be supported at all.’’

The trial, expected to last six weeks, began the same way Cadden’s trial did last winter, with the lead investigator from the Centers for Disease Control as the prosecution’s first witness.

Dr. Benjamin Park described the fear he felt when he learned the source of the outbreak: 17,000 vials of medication that had been injected into 14,000 people.

“We were very concerned that this could be a disaster, a mass casualty type of event,’’ Park testified. “I remember being very worried that this was the tip of a massive iceberg. I felt like I was standing over a cliff and couldn’t see the bottom. I was that scared.’’

Maria Cramer can be reached at mcramer@globe.com. Follow her on Twitter @globemcramer.