Dean Skelos, 67, of Long Island and his 32-year-old son, Adam, surrendered at the FBI's offices in lower Manhattan as a criminal complaint was unsealed against them in federal court, where they were expected to appear later in the day.
In a statement, Dean Skelos said he expected to be exonerated at trial.
"I am innocent of the charges levelled against me. I am not saying I am just not guilty, I am saying that I am innocent," he said. A lawyer for his son did not immediately return a message seeking comment.
Authorities said Dean Skelos — New York state's most powerful Republican official —has used his position as a carrot since at least 2010, taking official actions in return for payments to his son.
According to court papers, some evidence was obtained through court-authorized wiretaps on cellphones used by the father and son.
The complaint said Dean Skelos bragged to his son recently in one conversation after he was re-elected majority leader in January, a post he shared with another senator from 2011 to 2013: "I'm going to be president of the Senate. I'm going to be majority leader. I'm going to control everything."
The charges were unveiled four months after former Assembly Speaker Sheldon Silver, D-Manhattan, was charged with accepting nearly $4 million in payoffs. Silver, maintaining his innocence, gave up his leadership post but is keeping his legislative seat as he fights the charges. Earlier this month, Silver's son-in-law was charged in a $7 million Ponzi scheme.
U.S. Attorney Preet Bharara told a news conference that the charges are more proof that public corruption is a chronic problem in the state. The prosecutor was subdued in his depiction of wrongdoing after a federal judge recently criticized him for overdoing the publicity surrounding Silver's January arrest.
The complaint said Dean Skelos used his position to extort money from others, including hundreds of thousands of dollars from a senior executive of a major real estate development firm who was co-operating with the government.
Dean Skelos promoted and voted for real estate legislation sought by the developer, including some pertaining to rent regulation and property tax abatements, the complaint said.
Skelos said last month he was co-operating fully and would not resign his leadership post. He's hired an attorney in response to the investigation, which focuses on whether Skelos influenced Nassau County's decision to award a 2013 contract to Arizona-based AbTech.
AbTech did not immediately return a message seeking comment Monday.
Adam Skelos worked for the company as a consultant. The complaint said AbTech, which was only identified as an "Environmental Technology Company," more than doubled its monthly payment to Adam Skelos after the $12 million contract was approved.
AbTech has said it is co-operating with authorities and is not considered a target in the probe.
"The process through which local authorities selected AbTech was comprehensive and diligent, involving several levels of Nassau County government," the company said. "AbTech is proud ... to have earned this contract after a thorough and fair review process conducted by Nassau County."
U.S. Attorney Preet Bharara's office has not commented on the case. Bharara has called Albany a "cauldron of corruption."
Prosecutors called a news conference for noon. Dean Skelos has represented a portion of Nassau County on Long Island in the state Senate since he was elected in 1984. He was elected to the Assembly in 1980.
An attorney, Skelos is known as a shrewd negotiator and a frequent ally to Gov. Andrew Cuomo, a Democrat. He is the seventh top lawmaker to face criminal charges in the past six years. Since 2000, 29 New York lawmakers have left office because of criminal or ethical issues.
Another top Senate leader, Sen. Thomas Libous, R-Binghamton, has pleaded not guilty to a federal charge that he lied to the FBI about using his clout to arrange a job for his son, who was convicted earlier this year of filing false income tax returns.
Associated Press writers John Kekis, Michael Virtanen and David Klepper in Albany contributed to this report.
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