Joseph Gray resigned before he was to be interviewed by police investigators, the first step in the department's disciplinary process.
Gray's attorney, Harold Levy, had requested that any department trial be postponed until after the criminal case was concluded, but NYPD officials refused.
If a department trial had been held, Levy said, he believed Gray would have been found guilty, and that would have prejudiced his criminal case.
"I saw nothing to be gained by Officer Gray's being interviewed today, and he has resigned from the police department," Levy said.
Gray, a 15-year veteran, was indicted on manslaughter and other charges in the deaths Aug. 4 of 24-year-old Maria Herrera, her 4-year-old son, Andy, and 16-year-old sister, Dilcia Pena. Herrera was eight months pregnant at the time and her son was delivered, but was declared stillborn.
Gray had allegedly been drinking for up to 12 hours before the accident. An NYPD investigation revealed that he and other officers drank beer in a police parking lot, then moved on to a strip club that had been declared off-limits to officers.
In the wake of the accident, three officers on probation were fired and 14 others were transferred, suspended or had their job descriptions changed.
Gray, 41, left police headquarters Tuesday morning without being seen by reporters. But as he walked into the building, Juan Herrera, brother-in-law of Maria Herrera, yelled "He's a killer!" in Spanish.
Gray has expressed his sympathy to the victims' family.
When asked what Gray's career plans were, Levy wouldn't comment except to say his client had many skills and should not have trouble finding work.
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