Editor's Note: (A version of this story ran in October 2021. It has been updated with additional developments.)
(CNN) West Virginia Sen. Joe Manchin's long-standing financial ties to the coal industry face scrutiny after sources familiar with high-level negotiations told CNN he would not support the climate provisions of his party's proposed economic package.
The senator has not yet issued a public statement about his opposition, though his spokesperson said Thursday evening that Manchin wished "to avoid taking steps that add fuel to the inflation fire."
But climate advocates on Friday morning were quick to point to Manchin's longtime ties to the coal industry.
Manchin, whose vote is crucial to passage of President Joe Biden's domestic policy priorities in an evenly divided 50-50 Senate, had holdings in 2021 valued at between $1 million and $5 million in Enersystems, Inc., the coal brokerage business he founded, according to a recent financial disclosure form.
In 2021, he made more than $536,000 from his Enersystems holdings, the filings show. That's more than three times his $174,000 annual Senate salary.
"Manchin is a walking conflict of interest," Craig Holman, a lobbyist for the liberal watchdog group Public Citizen, previously told CNN. "And what makes it all the more troubling is that he's the 50th Democratic senator, which gives him enormous sway over climate change policy."
The debate over Manchin's coal interests also highlights what critics say are lax congressional ethics rules that give federal lawmakers broad leeway to regulate industries in which they have financial interests. In addition to his pivotal role on the domestic policy bill, Manchin helps set US energy policy as chairman of the Senate's Energy and Natural Resources Committee. He has served on the panel since entering the Senate in November 2010, after he won a special election to replace the late West Virginia Sen. Robert Byrd.
Congressional rules also permit federal lawmakers to trade individual stocks -- as long as they disclose the transactions and do not financially benefit from insider information.
"We have a system where a member of Congress can be invested heavily in, for example, the coal industry and then be responsible for overseeing climate policy," Delaney Marsco, senior legal counsel for ethics at the nonprofit Campaign Legal Center, said in 2021. "It doesn't make sense."
In a written statement in October, a Manchin spokesperson said the senator "is and has been in full compliance with Senate ethics and financial disclosure rules."
"He continues to work to find a path forward on important climate legislation that maintains American leadership in energy innovation and critical energy reliability," the statement added.
The fresh attention to Manchin's energy interests comes as Biden and Democrats are racing this week to complete a framework for a domestic policy bill that includes many of the President's priorities on the economy and climate. To avoid a filibuster by Senate Republicans, Democrats are relying on a budget process that requires the support of all 50 senators who caucus with them. That gives Manchin, a moderate member of the caucus, enormous sway over the negotiations.
Manchin has resisted climate provisions since the earliest days of work on the bill -- including the so-called Clean Energy Performance Program, which had been a cornerstone of Biden's climate plan, aimed to reward utilities for switching to clean energy sources, such as wind and solar, and penalize those relying on coal and gas.
Manchin signaled in October he wouldn't support that program, saying he didn't support a program that would push utilities to move to clean energy faster than they were already doing. Manchin had also cited concerns that switching to clean sources of energy could mean energy would be more unreliable than continued use of fossil fuel.
"The transition's already happening," Manchin told CNN recently. "So I'm not going to sit back and let anyone accelerate whatever the market's changes are doing."
Even without the clean electricity program, Manchin could not get behind the climate provisions in the latest version of an economic package -- including tax credits for clean energy and electric vehicles -- citing increased federal spending as a main driver of inflation.
Manchin has never made any secret of his ties to coal. He's a former governor of the country's second-biggest coal-producing state, and he founded Enersystems before entering politics.
The senator also has a stake in another firm run by his son, Farmington Resources Inc. Its services include "support activity" for coal and metal mining and drilling oil and gas wells, according to corporate filings with the West Virginia secretary of state's office.
Between 2011 and 2020, the Democrat made between $4.9 million and $5.1 million from coal-related enterprises, according to an analysis by Open Secrets, a nonprofit that tracks money in politics.
The organization also estimates Manchin's net worth at anywhere from $4.3 million to $12.8 million. Lawmakers are only required to disclose their assets and liabilities in broad ranges, making it impossible to determine precise values.
Manchin's Senate campaign also benefited from of a flood of political contributions from the energy industry in recent months. He took more than $400,000 from energy interests during the July-to-September 2021 fundraising quarter, according to a CNN review of that filing with the Federal Election Commission.
Donors in that period included billionaire oil tycoons Harold Hamm, the chairman of Continental Resources; Richard Kinder, the executive chairman of energy infrastructure company, Kinder Morgan; and Trevor Rees-Jones, who founded Chief Oil and Gas.
He also received donations from an array of energy-related political action committees in those months, including those affiliated with ConocoPhillips; utility companies such as Exelon and Dominion Energy; and Texas oil producer Pioneer Natural Resources.
Manchin, who isn't up for reelection until 2024, raked in nearly $1.6 million in the third quarter of 2021 -- as he and another centrist Democrat, Arizona Sen. Kyrsten Simena, emerged as key players in the negotiations over their party's sweeping domestic policy proposals.
Manchin's energy holdings -- and his actions that benefit the coal industry -- are legal under rules that police potential conflicts of interest in the Senate.
The rules differ dramatically, depending on the branch of government.
Executive branch employees, for instance, are generally required to recuse themselves from decision making when their financial interests conflict with their official duties. They face potential criminal and civil charges for failing to do so. Those appointees also must abide by additional ethics rules established by the President -- such as not engaging in decisions involving their former employers. Appointees in the executive branch can and do seek and receive waivers of ethics rules in limited circumstances.
It is against the law for federal judges to hear cases in which they have any legal or financial interests, but the law doesn't impose penalties for violations.
In Congress, meanwhile, lawmakers only must recuse themselves from taking official actions in a narrow set of circumstances: If they or their immediate family members are in a small group that would benefit from the legislative action.
But a lawmaker who owns a dairy farm, for instance, can still make policy decisions that affect the entire dairy industry because those actions "also have a broad, general impact on his state or the nation," according to the Senate's ethics manual.
And requiring lawmakers to recuse themselves from decisions that benefit certain industries could end up hurting their constituents "who are entitled to have their elected representatives represent them by voting and fully participating in all aspects of the legislative process," the manual adds.
Watchdog groups are urging Congress to revisit its conflict-of-interest standards.
One bipartisan measure, authored by Democratic Rep. Abigail Spanberger of Virginia and Republican Rep. Chip Roy of Texas, would require House members, for example, to place a broad array of holdings in blind trusts. Investments in widely held funds, such as mutual funds, and Treasury bonds would be exempted.
"The rules are currently insufficient to meet the challenges, particularly if you take into consideration that the American people really view corruption as a huge problem," said Dylan Hedtler-Gaudette of the Project on Government Oversight. His group supports the blind trust bill.
"The appearance of impropriety is just as bad as the real thing," he added, "because that drives the way people feel about politics and government."
This story has been updated with more information.