This article is from the archive of our partner National Journal

It's been less than two weeks since CNN first reported that the Justice Department will soon charge Sen. Robert Menendez with corruption. But the New Jersey Democrat has been preparing for a possible legal battle for going on two years, amid rumors of shady conduct with a longtime donor.

Menendez spent thousands of dollars from his campaign coffers in December 2013 for legal counsel related to two ethical probes launched in early 2013, one from DOJ and another from the Senate Ethics Committee. In January 2014, with the blessing of that same Ethics Committee, the senator established the Robert Menendez Legal Expense Trust, which has helped him pay for the two ongoing matters ever since—and will cover future expenses.

There are too many moving parts to anticipate exactly how much Menendez's total defense in the DOJ case might cost, but past legal battles involving members of Congress suggest it could be in the thousands to millions of dollars. His legal expenditures related to both probes have so far been high: By the end of September 2014—20 months after the Senate ethics announcement, but more than five months before the CNN story broke—Menendez had already spent $1 million. In a three-month period in mid-2014, he burned through $250,000.

The senator is not an exorbitantly wealthy man, and devoting significant time and money to a legal fight could be draining—both financially and politically. Menendez is up for election in 2018, and there's no telling whether the potential case against him will be resolved by then.

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"It's really impossible to put any kind of reasonable number" on how much his total defense could cost, said Kenneth Gross, a lawyer at a Washington law firm who specializes in political law and ethics. "But lawyers are not cheap."

Menendez allegedly accepted favors from a longtime friend and donor, Florida eye doctor Salomon Melgen, in exchange for the senator's political sway. According to Gross, Menendez can use a combination of funds—including money from personal, campaign, and PAC coffers—to provide for his legal defense.

Menendez's net worth, about $450,000 according to the latest available data, is paltry compared with his fellow members of Congress. He ranks 82nd in the millionaires club that is the U.S. Senate, where in 2013 the average senator was worth more than $10 million.

By 2014's end, Menendez's campaign committee had a little over $1.45 million cash on hand. And his New Millennium PAC, another potential source of funds, had about $140,000.

"He could settle it, it could be dropped, it could have to go to court," said Gross, of law firm Skadden, Arps, Slate, Meagher & Flom. "So it could be from thousands to millions, depending on whether we're talking about a full trial and appeals, or anything else."

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The case of former Sen. Ted Stevens of Alaska highlights just how high legal bills can climb. Stevens was charged in 2008 for concealing expensive gifts in financial disclosure statements. All in all, the legal fees associated with his trial totaled about $5 million.

The Stevens case, though, may have been an outlier: Gross said it was so expensive because Stevens went through a full trial and appeals process. "That was the full monty," he said.

As news reports continued to come out about Menendez's relationship with Melgen in 2014, his now-more-than-a-year-old trust fund took in more than 120 contributions, including money from Hispanic-market radio company Spanish Broadcasting Systems, which Menendez was scrutinized for trying to help in a 2003 merger. Last year, the trust took in $866,000 and spent $762,000, according to OpenSecrets.org, the website of the nonpartisan research group the Center for Responsive Politics.

Gross said senators don't typically have legal defense funds lying in wait for a potential legal misstep. Rather, funds are established if senators have a "reasonable anticipation" of needing them. For Menendez, that's years of ethical probes.

The rules governing which pots of money can be used to pay for a senator's legal fees are complex. Larry Noble, senior counsel at the Campaign Legal Center who served as general counsel at the Federal Election Commission from 1987 to 2000, said that the regulations are designed to ensure that contributions are used for a member's defense and only their defense—no personal or campaign uses allowed.

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Bill Allison, a senior fellow at the Sunlight Foundation, said that PACs and campaign committees can both contribute to a senator's legal defense trust, which must disclose all donors. Outside of the trust, a senator could use PAC money—including from his own leadership action committee—to pay legal fees, provided that the PAC is involved in some way in the legal charges.

In the case of Menendez, part of the Justice Department's probe involves the senator's leadership PAC, New Millennium PAC. Thus, Menendez's committee could provide funds via the trust—which it in fact did, giving $10,000 in June 2014—or outside of the trust, such as directly to a legal team. Senators can also ask the FEC for approval to use campaign funds to directly pay legal fees, provided that the charges relate to the senator's official or campaign duties, Allison said.

The allegations against Menendez are directly related to his political office, so at least part of his $1.45 million campaign fund could hypothetically be used for legal fees. Menendez can't receive any financial help from corporations, labor unions, or lobbyists, although individuals are allowed to contribute to his trust. All trust donations from legal entities—including individual donors—are capped at $10,000 per year.

Elliot Berke, a Washington-based managing partner of law firm Berke Farah who has represented members of Congress, said there's "ample precedent" for a senator using campaign funds to pay for legal expenses that stem from a legal matter related to his campaign or official duties. But trouble can arise when allegations are related to more personal conduct, he said. Then it becomes less clear-cut whether campaign funds can be used.

Noble cites former Sen. Larry Craig as an example of the misuse of campaign funds for a legal defense. Craig was penalized by the FEC for using more than $200,000 from his campaign fund to pay legal fees stemming from his arrest in an undercover sex sting at a Minneapolis airport in 2007. He claimed he could use campaign money because he was traveling through Minneapolis on official business; the FEC disagreed.

Now, Menendez's legal team is likely laying the groundwork for his defense. And with each hour that passes during the process, the bills get bigger.

"All of that takes time and money," Gross said. "Everything takes time and money."

This article is from the archive of our partner National Journal.

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