DEDHAM, MASS. (WHDH) - Proceedings got underway Wednesday in the second trial for a man accused of killing a Weymouth police officer and a bystander in 2018. 

Emmanuel Lopes has been charged with murder in the case. Months after a jury was unable to reach a verdict in his first trial, Lopes was back in court as the prosecution and the defense delivered opening statements in his new trial. 

Following opening statements, the court heard from the first of seven witnesses scheduled to take the stand. 

“He shot the officer five times in the head and three times in the chest,” said witness William McGuiness.

McGuiness described how Lopes allegedly hurled a rock at Weymouth Police Sgt. Michael Chesna, knocking him to the ground back in July, 2018. McGuiness said Lopes then allegedly grabbed Chesna’s gun, stood over him and opened fire. 

In addition to Chesna, prosecutors said Lopes also shot and killed 77-year-old Vera Adams, who was sitting in her sunroom as Lopes ran through backyards trying to get away from police. 

Years after these shootings, the details of the case remained excruciating for the victims’ families on Wednesday, with family members seen crying in court.

While the prosecution discussed its case, Lopes’ legal team in opening statements continued to maintain their client is not criminally responsible for the murders. 

“His behavior is irrational, bizarre, and there is no explanation except for the fact that he was in a psychotic state when it happened,” a defense attorney said. 

In his own opening statement, a prosecutor responded, saying the prosecution plans to prove Lopes was criminally responsible. 

Jurors in Lopes’ current trial are being bused in to Norfolk County Superior Court in Dedham from Bristol County. 

Due back at the courthouse Thursday morning, jurors are at one point scheduled to leave Dedham to view the crime scenes.

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