This post has been updated.

The politically connected law firm Harris Beach on Friday filed with state Supreme Court today to quash a subpoena from Gov. Andrew Cuomo’s anti-corruption commission seeking more information on Sen. Michael Nozzolio’s outside income and law clients than what is currently revealed under state law.

But more broadly the Harris Beach filing takes on the commission’s jurisdictional authority over investigating the Legislature as a whole, knocking the Moreland Act-empowered panel for being nothing more than a “fishing expedition.”

“To interpret the Moreland Act as granting the Executive Branch jurisdiction to investigate the Legislature would result in plain contravention of New York’s separation of powers doctrine,” according to the filing.

Nozzolio, a western New York Republican, is a longtime counsel at the firm.

Updated: The firm Hiscock and Barclay also filed a motion to have its subpoena, leveled at partner and GOP Assemblyman Will Barclay, to be tossed out.

The filing states the subpoena “is overly broad, unduly burdensome and oppressive.”

Hiscock and Barclay also employ Democratic Sen. Neil Breslin, but he does not appear to have been the target of a subpoena. Breslin has said he would divulge his client list.

The Moreland Commission, Attorney General Eric Schneiderman and the governor have maintained the commission has the jurisdiction to investigate public corruption in the Legislature. The panel was deputized by Schneiderman in order to work around the separation of powers issue.

In the filing, Harris Beach attorney Karl Sleight argues the subpoena seeking more information from the law firm on Nozzolio’s activities violates the state’s Constitution and separation of powers.

“The Subpoena is invalid because it was issued by a Commission created by Governor Cuomo in excess of the his jurisdiction under the Moreland Act,” Sleight wrote in the filing. “The Commission’s objective to investigate the Legislature blatantly violates New York’s separation of powers doctrine. Further, the Subpoena itself improperly pursues indirectly through Harris Beach what the Commission is forbidden from pursuing directly from Senator Nozzolio.”

Sleight, of course, is a former executive director of the New York State Ethics Commission from 2001 through 2007 and served as a deputy attorney general.

The filing also takes direct aim at the Moreland Commission on Public Corruption’s purpose: Namely that it is really meant to force the Senate and Assembly to the bargaining table for an ethics deal.

“Coercive tactics aside, because the Commission was formed for an unlawful purpose — to allow the Executive Branch to investigate the Legislature — any such jurisdiction it seeks to assert over Harris Beach directly and Senator Nozzolio indirectly is unlawful,” Sleight wrote.

In a separate statement released by Harris Beach, Sleight said “it is ironic” that the commission seeking to investigate corruption “blatantly disregards the sacrosanct relationship of clients and their attorneys.”

“Allowed to continue unfettered, this far-a-field inquiry would adversely impact every individual and business in New York,” Sleight said in the statement. “The latest chapter of this wayward commission is another clumsy exchange that has only served to raise new ethics concerns about the government, and not solve them.”

186374798 Memo of Law Re QuashProtective Order HBROC 2152980 v1 by Nick Reisman

186380609 Hiscock and Barclay by Nick Reisman