The lawyer, Michael Sussman, alleged that the district attorney's office was in on the deception. And he said the episode demonstrated the need for a special state prosecutor's office to investigate every time police use deadly force.
"No one in the public should have any confidence" that district attorneys can fairly investigate the police departments they work with, Sussman said at a news conference.
He said his claims were based on "shocking details" in depositions he has taken during a federal lawsuit filed by the parents of Danroy Henry Jr., the victim in the 2010 shooting.
Henry, 20, of Easton, Mass., was shot through the windshield of his car as he drove away from a disturbance outside a bar in Thornwood, N.Y. Earlier in the day, he had played for Pace University's football team on Homecoming Day.
The Pleasantville police officer who shot him, Aaron Hess, said Henry was driving toward him and wouldn't stop. He fired from the hood of Henry's car.
Another officer, Ronald Beckley of the Mount Pleasant police force, also fired. But Beckley said in his deposition that he was firing at the person on the hood, not knowing it was Hess and believing it was "the aggressor."
Both officers testified before a grand jury and were cleared of wrongdoing. Hess is among those being sued by the Henrys.
Sussman alleged Thursday that Beckley's depiction of Hess as the aggressor was known within hours to Mount Pleasant police Chief Louis Alagno, the chief investigator, and to the district attorney's office.
Alagno's press release the next day, however, depicted Beckley as shooting at the car, not at the officer on the hood.
That was "a knowingly false statement by a person who is still a police chief," Sussman said. He suggested it should have disqualified Alagno from running the investigation.
In his deposition, Alagno said he did not include what Beckley said because "it was information we would present to the grand jury." His lawyer, Carl Sandel, said Thursday that he could not comment on an active lawsuit.
Sussman said the district attorney's office did nothing to set the record straight.
He said the early account meant investigators "have a script. ... The script shows a decision to protect the police."
It's not clear, however, that Alagno's early account affected the investigation as a whole.
Lucian Chalfen, a spokesman for District Attorney Janet DiFiore, noted that Beckley testified before the grand jury that cleared him and Hess. DiFiore said at the time that the investigation was "exhaustive and thorough," a sentiment repeated by Chalfen on Thursday.
Henry's father, Danroy Henry Sr., spoke briefly at the news conference. He said what he's heard from witnesses during the lawsuit adds to his doubts about an autopsy finding that his son's blood-alcohol level was above the legal limit for driving. The family has always denied that D.J. was drunk.
Sussman said he still has 50 or 60 depositions to take. If the case goes to trial, he said, it would likely be in 2014.