Politicians holding any kind of office can get themselves into legal trouble. Lately, though, state House speakers have been especially prone to indictment.

Facing federal corruption charges, Democrat Sheldon Silver of New York on Sunday agreed to relinquish his duties as Assembly speaker.

Silver, who is accused of accepting bribes in the form of legal fees, was the fourth speaker to enter into legal peril over the past 10 months.

“It’s not all 50 states, but four out of 50 is pretty bad,” said Brendan Nyhan, an expert on political scandals at Dartmouth College.

Last year Bobby Harrell of South Carolina resigned following indictment, while Gordon Fox of Rhode Island did the same following a federal raid of his house and his legislative office. Earlier this month, Republican Mike Hubbard was re-elected as speaker of the Alabama House, despite being indicted in October on nearly two-dozen felony corruption charges. Hubbard denies any wrongdoing but faces a possible trial this spring.

Alabama House Speaker Mike Hubbard (AP/Brynn Anderson)

Each case is different, but all concern allegations of corruption or ethical abuses. This cluster of indictments opens up the question of whether there is something in the nature of the job of speaker that makes corruption more likely to occur.

Here are five potential explanations as to why some speakers may find themselves in hot water:

1. Lots of Power

Speakers are powerful figures, often able to control their chambers in a hierarchical way not available to many other political leaders.

“The speaker is at the top of that pyramid in a way that is rare even for the Senate,” said Thom Little, research director for the State Legislative Leaders Foundation. “The power is greater pretty much than any other legislative office.”

Speakers can kill a bill quietly, Little notes, simply by assigning legislation to hostile committees. Governors may need to issue veto messages, but speakers can do much of their work secretly.

2. …But Not Much Scrutiny

Speakers may be powerful, but they receive comparatively little media attention. Most people can name their state’s governor, but few people know who the speaker is.

“Legislative leaders have a great deal of power but face very little scrutiny,” Nyhan said. “That’s a combination that can certainly lead to corruption, especially in states where that tends to be more of a problem.”

Former South Carolina House Speaker Bobby Harrell (AP/Rainier Ehrhardt)

3. Limited Political Pressure

Speakers not only receive less media attention than governors, they also answer to fewer voters than any comparably powerful politician.

They might represent districts that account for a hundredth, or a hundred-fiftieth, share of their state’s population. “They’re elected locally, but their impact is statewide,” said Pam Wilmot, executive director of Common Cause in Massachusetts, where three of the last four speakers resigned and pleaded guilty to criminal charges.

Not only are their districts small and generally safe, but often the majorities they lead are safe as well. In New York, Rhode Island and South Carolina, it’s been years since party control has changed in the House chambers. That’s not the case in Alabama, but there Republicans now control the whole of state government.

“When you have one chamber controlled by the other party, they’re looking at everything you do,” Little said.

Former Rhode Island House Speaker Gordon Fox (AP/Steven Senne)

4. Tendency to Play Let’s Make a Deal

Speakers are able to direct enormous sums of money. And, in an era where caucus leadership PACs can dominate legislative campaign fundraising, they need enormous sums of money.

“Speakers have enormous power and the duty to raise large amounts of political money,” said former North Carolina Speaker Joe Hackney.

Yet, he notes, the job itself doesn’t pay that much. “The confluence of those three things make it really dangerous territory.”

Hackney himself became speaker after his predecessor, Jim Black, became embroiled in a set of corruption scandals.

Not all speakers go looking for trouble. But the nature of the job is making deals, so a politician with that job has plenty of opportunities to cut himself in.

“There is a lot more deal-making in the legislative process than there is in the executive branch,” said Wilmot, the Common Cause official.

5. Tempting Targets for Prosecutors

Making public corruption cases is always tough for prosecutors -- there generally isn’t tangible evidence like drugs waiting to be seized, quips Nyhan, the Dartmouth government professor -- but elected officials still make tempting targets for ambitious prosecutors -- particularly those as prominent as a state House speaker.

There have been no shortage of legislators in New York who have faced indictment in recent years, but the power and prestige Silver held as the longtime speaker made him stand out.

“Prosecutors may choose to go after the big fish,” said Nyhan. “They may choose to target the most powerful legislators in places where corruption is a problem, both as punishment and as a signal to others.”

Correction: An earlier version of this story stated that Gordon Fox had been indicted. He was not.