ALBANY (CBSNewYork/AP) — New York Assembly Speaker Sheldon Silver is taking a leave of absence from his law firm as he fights federal corruption charges.

New York City-based Weitz & Luxenberg announced the separation Wednesday. President Perry Weitz says the firm was “shocked” to learn about the accusations against Silver.

The 70-year-old Manhattan Democrat was taken into custody last Thursday on federal charges he took nearly $4 million in payoffs and kickbacks.

Some of the charges relate to allegations that Silver collected money for securing state grants for a doctor who then referred cases to the firm. Weitz says the firm had no knowledge of the alleged arrangement.

Silver has said he expects to be exonerated. If convicted, he could face a sentence of up to 100 years in prison.

The Assembly’s Democratic majority announced Tuesday that Silver had agreed to relinquish his position as speaker, which he has held for 21 years.

The decision announced by Majority Leader Joseph Morelle came after Democratic lawmakers met behind closed doors for two days to discuss their response to the turmoil that has threatened one of the longest careers in American state politics.

“He said to me he will not impede the transition,” said Morelle, surrounded by most of the other 105 Assembly Democrats. “We’ll have a vacancy on Monday.”

“I don’t know what decision my colleagues made,” Silver told reporters later. “I made a decision that I will not hinder this process.”

As majority leader, the No. 2 post in the chamber, Morelle would be the acting speaker from the moment Silver resigns until the lawmakers formally convene again Monday. At that point, they plan to amend their rules to keep him as interim speaker until Feb. 10.

That’s intended to give any other member a chance to express interest and explain how he or she would lead and make the selection a more open process than it has been in the past, Assemblyman Thomas Abinanti said.

“I think what carried the day is we want to enter the budget process united,” he added, with a new speaker who has the clear, legitimate backing of the Assembly’s two-thirds Democratic majority when he or she goes to negotiate with the governor.

Earlier this week, Silver’s spokesman said he would not be stepping down, but would temporarily cede power to a small group of top lawmakers to undertake various responsibilities.

“I think the plans to have Shelly have a committee take over his duties ran into the rank-and-file saying absolutely not,” former Assemblyman Richard Brodsky told WCBS 880’s Sean Adams.

Assemblywoman Nicole Malliotakis called Silver’s departure as speaker a new chapter for hope in Albany, one that’s long overdue, 1010 WINS’ Glenn Schuck reported.

“I believe Speaker Silver has been the biggest obstacle in really achieving government reform and ethics reform in this state,” she told Schuck. “Now that he’s gone, this really is a new day for New Yorkers. We can really put together a government that all New York can be proud of.”

He has led the Assembly for 21 years, the second-longest tenure of any sitting speaker in the nation.

He declined to respond when asked if he would resign. It is unclear whether Silver would do that or whether his tenure will be formally ended Monday by legislative action.

He has said he has no plans to resign his seat in the Assembly.

But even the idea of remaining in the Assembly is not sitting well with some New Yorkers, CBS2’s Diane Macedo reported.

“I think people are innocent until they’re convicted, but again if it is impeding the process one would think he would step aside so that legislation and government can continue,” said Nancy Beck, of Manhattan.

“I think he should not be in the picture at all, he should resign,” said Ingrid Menendez, whose daughter goes to school on the lower East Side.

“It’s been a long time coming. People knew he was a crooked and it should’ve happened years ago,” said Brooklyn resident David Lubin.

Members of the Assembly said Silver’s criminal charges had become a distraction and a problem for entire chamber.

“There is a strong sense among members it would be best for the speaker to step down and for this body to elect a new speaker,” Assembly member Patricia Fahy (D-Albany) said Tuesday. “There is a lot of hard work ahead to move ahead and unite the body behind a new speaker who can best represent the entire state, champion reforms and restore confidence in the Assembly.”

Silver had one vocal ally remaining. Mayor Bill de Blasio has called Silver “a man of integrity” and said Tuesday that he shouldn’t resign.

He added that people have to respect the Assembly’s decision, but “it’s crucially important” that there is leadership that’s fair to the city, which often doesn’t get its fair share from the state government.

(TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)