PITTSBURGH (AP) — A gunman who killed 11 worshippers at a Pittsburgh synagogue ranted incessantly on social media about his hatred of Jewish people before the 2018 attack, according to evidence introduced at his federal death penalty trial on Tuesday.

Prosecutors are trying to show Robert Bowers was motivated by extreme hostility toward Jews when he opened fire at the Tree of Life synagogue during Sabbath services and committed the deadliest antisemitic attack in U.S. history.

The 50-year-old truck driver is charged with 63 criminal counts, including hate crimes resulting in death and the obstruction of the free exercise of religion resulting in death. Some of the charges carry a potential death sentence.

Prosecutors said they planned to wrap up their case Wednesday afternoon. It wasn't clear if the defense planned to call any witnesses.

With the trial in its third week, testimony turned toward Bowers’ use of Gab — a social media platform popular with the far right — to advance his antisemitic views.

Bowers’ Gab profile said “Jews are the children of Satan,” and he posted, liked or shared a stream of virulently antisemitic content, according to dozens of examples provided to the jury on Monday and Tuesday. Bowers called Jews “public enemy number one,” according to a post read by an FBI agent, spoke approvingly of Adolf Hitler and the Nazi extermination of Jews, and shared an image that said “the only good Jew is a dead Jew.”

William Braniff, a terrorism expert at the U.S. Department of Homeland Security who reviewed Bowers’ social media activity, told jurors that Bowers used symbols and terms associated with Nazi, antisemitic and white supremacist ideologies.

On the morning of the attack, Bowers posted about HIAS, a Jewish agency that helps refugees resettle in the United States. Dor Hadash, one of the three congregations that shared the Tree of Life building, worked with HIAS.

“HIAS likes to bring invaders in that kill our people. I can’t sit by and watch my people get slaughtered. Screw your optics, I’m going in,” Bowers posted.

Working to spare his life, Bowers' lawyers have acknowledged he was the shooter but are trying to raise questions about motive. The defense has suggested he did not act out of religious hatred but rather a delusional belief that Jews were enabling genocide by helping immigrants come to the U.S.

Survivors have previously testified about the terror they felt that day as Bowers barged into the synagogue and shot everyone he could find, while police officers testified about exchanging gunfire with Bowers, who surrendered after being shot three times. Seven people were wounded in the rampage, including five police officers.

Also Tuesday, the judge denied a request from Bowers' lawyers to hold a hearing and potentially limit victim impact testimony during the anticipated penalty phase of the trial.

The defense had argued the “inherently emotional and potentially overwhelming nature" of testimony from survivors and victims' relatives could be prejudicial to Bowers and unfairly influence jurors who must decide whether to sentence him to death or life in prison.

In a ruling, the judge said a hearing to review the government's proposed evidence at the sentencing phase was not warranted, but cautioned prosecutors to “stay well clear of any testimony that might cross the line.”

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