Assistant Capt. Richard Smith, who attempted suicide right after the crash, left St. Vincent's hospital on Thursday, said hospital spokesman Jim McMahon.
Meanwhile, U.S. Attorney Roslynn Mauskopf was to announce Friday that she is taking over the criminal probe of the crash from the borough's outgoing district attorney, two law enforcement officials said.
Mauskopf, whose district includes Brooklyn and Staten Island, and District Attorney William Murphy agreed that differences between federal and state rules governing immunity of witnesses, grand jury testimony and potential criminal sentencing made a federal prosecution more desirable, a law enforcement official familiar with the decision told The Associated Press on Thursday on condition of anonymity.
The New York Police Department and the Coast Guard will continue to investigate, another law enforcement official said. The FBI is not expected to be involved, the source said.
The decision was expected to be announced at the district attorney's office.
Concurrent probes by the National Transportation Safety Board, NYPD, Coast Guard and city Department of Transportation have focused on the actions of Smith and the captain, Michael Gansas.
In conversations with emergency responders in the hours after the Oct. 15 crash, Smith and Gansas indicated that Smith had slumped over the controls and Gansas had tried unsuccessfully to pull him away and take over.
But one of the ship's mates said Smith was erect behind the controls in the minutes leading up to the crash and Gansas was not with him in the ship's wheelhouse, an apparent violation of city rules.
Smith and Gansas have not spoken with investigators. Gansas refused to answer questions in a hearing, citing his constitutional right against self-incrimination.
On Thursday, a hearing officer with the Department of Transportation recommended that the city fire Gansas. Gansas' attorneys can appeal the recommendation through a grievance with the DOT or through the city's Office of Administrative Trial Hearings.
A telephone call to the office of Gansas' attorney William Bennett was not immediately returned Thursday.