Prosecutors said late Wednesday they were holding off on a decision to try the driver of a sightseeing bus that plowed into a crowded Times Square plaza until they receive a full toxicology report.
Preliminary drug and alcohol tests for William Dalambert came back negative, a spokeswoman for the Manhattan District Attorney's office said.
"We are taking this matter seriously," the spokeswoman, Joan Vollero, said in a statement. She said prosecutors are conducting a thorough investigation.
Police said there was no evidence Dalambert had been drinking, but he failed a field sobriety test after Tuesday's crash, leading the department to float the theory that he may have been high on drugs.
The New Jersey man was to be arraigned on Wednesday on charges of driving while impaired, but the decision of the district attorney's office appeared to short-circuit that development.
Leaving police custody Wednesday night with Dalambert, Dalambert's attorney said, "We are very pleased with the investigation to date," and called it "very responsible."
Dalambert was at the wheel of a Gray Line bus that crashed into another double-decker tourist bus on Tuesday before traveling onto a sidewalk at Duffy Square, the location for the TKTS discount Broadway ticket booth.
The accident sent 14 people to the hospital with non-life-threatening injuries.
Dalambert's driving record includes 20 suspensions, though motor vehicle records show all of his privileges had been restored and he has a valid New Jersey license, according to state motor vehicle spokeswoman Sandy Grossman. His record includes license suspensions for non-payment of child support, uncompleted paperwork and fines on top of previous violations for not paying insurance, Grossman said.
He has a commercial license to carry passengers and endorsements to drive a number of other vehicles, including a motorcycle, a tanker, double and triple trailers and school buses, Grossman said.
There was no immediate response to a phone message left on Wednesday with Gray Line. On Tuesday, a spokesman for Gray Line's parent company said, "Our hopes and prayers are with the injured, and we are cooperating with the authorities."
Manhattan has seen a proliferation of the double-decker buses since 2005, when there were eight bus companies. Now there are 14 bus companies, operating more than 260 buses, but accidents are rare.
On June 18, a woman was struck by a CitySights double-decker tourist bus in Greenwich Village and was seriously injured.