His power unbending, his whims often unexplained, Sheldon Silver, in his two decades as speaker of the State Assembly, became a seemingly indestructible presence at the nucleus of the New York political world, a steady advocate for liberal causes and a master tactician in Albany’s closed and entrenched way of governance.

But Mr. Silver’s arrest on Thursday on corruption charges has thrown into question that arrangement, in which the governor and the leaders of the two chambers of the Legislature privately decide the most crucial policies of the state. It is a potentially seismic shift in power whose reverberations may be felt throughout the state, from the speaker’s home district on the Lower East Side of Manhattan to the grounds of the State Capitol.

Until now, Albany lawmakers accustomed to what prosecutors called a “show-me-the-money culture” have taken comfort in knowing that their most powerful figure was unassailable — untouched despite years of inquiries, suspicions and rumors of impropriety.

It appears that the crux of the matter is that Silver was paid large sums by his law firm for work which either did not justify the payments, or for which he did no work.

In essence, he is accused of using this law firm to launder bribes.

Here is hoping that he sees the writing on the walls, and starts singing like a canary.

Clearing out the cesspool in Albany would be a good thing.