Opening statements began Monday in the trial of a man accused of trying to kill his former boss outside of a deli in Chappaqua.

Police say Hengjun Chao, of Tuckahoe, fired a 20-gauge shotgun at Dr. Dennis Charney outside Lange's Deli on King Street in August 2016.

Chao had previously worked as a researcher at the Icahn School of Medicine at Mount Sinai. Charney was his boss and fired Chao in 2010 for allegedly manipulating data while Chao was a researcher at the hospital. While Chao was initially fired back in 2010, the attack occurred just after his final appeal to be reinstated was rejected last year.

In his opening statement, Chao's lawyer, Stewart Orden, argued it was Charney and several other colleagues who were perpetuating research fraud.  Orden contends they tried to hide the harmful effects of a drug used to treat depression, particularly in teenagers.

The defense claims Chao shot Charney not to harm him, but to garner publicity for what he considers large-scale fraud by his former boss.

"He went there to fire a gun ..not even to injure ...to fire a gun in the direction of the man he holds responsible...in part for the deaths of teenagers,” he said.

Chao and Charney are both expected to take the stand during the trial.