Rep. Rodney Frelinghuysen paid lawyers in New Jersey and Washington nearly $32,000 this spring after an ethics complaint was filed over a fundraising letter he sent complaining that a bank's attorney was a "ringleader" of a group organizing protests at his offices, campaign filings show.

"It was a prudent move given the politically motivated ethics complaints that came from the professional left," Frelinghuysen campaign adviser Mike Duhaime said when asked about payments of $27,000 to Wiley Rein in Washington and $4,900 to Herold Law in Warren.

The payments were disclosed in a filing with the Federal Election Commission that Frelinghuysen made on Wednesday.

The Campaign for Accountability asked the Office of Congressional Ethics to investigate Frelinghuysen in May after reports he had sent a fundraising solicitation to a board member of Lakeland Bank that included a handwritten note about a bank executive being part of the group organizing regular protests at his office.

“P.S. One of the ringleaders works in your bank!” Frelinghuysen wrote. Attached to the letter was an article from Politico that quoted the employee, Saily Avelenda of West Caldwell.

Avelenda, an attorney who serves as assistant treasurer for NJ 11th for Change, said she was confronted with the letter by her boss and asked to write a letter describing her efforts with the group. After writing the letter, she decided to resign.

“The conversation about the letter was either the third or the fourth time I was asked to explain my activities,” she said Thursday. “I could not see how I could continue to serve as in-house counsel for a bank when my boss, a board member and the CEO were that involved in my outside activities.”

Wiley Rein's website says it has "the premier election law & government ethics practice in the country." Its lawyers include a former chairman of the Federal Election Commission and a former chief counsel to the House and Senate ethics committees.

Under House rules, anyone can file a complaint with the Office of Congressional Ethics. The office reviews complaints from the public, but the most it can do is refer those it considers valid to the House Ethics Committee, which would conduct its own private review. A new member to that committee, which has the power to sanction and even expel members, is Rep. Leonard Lance, a Republican from Hunterdon County.

The executive director of the group that filed the complaint against Frelinghuysen, Daniel Stevens of the Campaign for Accountability, said the group does not disclose its donors but it has a record of being nonpartisan.

“One of the first things we did was file an ethics complaint against nearly a dozen members of Congress, Republicans and Democrats,” he said. That complaint centered on contributions members received from the payday lending industry around the time Congress took action affecting the industry.

“We focus on holding parties accountable,” Stevens said.

In its complaint, the center says Frelinghuysen would have violated House rules against using his official position for personal gain if he tried to get the bank to fire Avelenda or make her employment more tenuous.

Frelinghuysen, R-Harding, is a 12-term incumbent who could be facing his toughest re-election in decades next year because of changes in his district and a surge in activists opposed to the policies of President Donald Trump.

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Mikie Sherrill, a Montclair resident campaigning to be Frelinghuysen's Democratic challenger next year, said in a statement the congressman should be investigated for targeting Avelenda for exercising her First Amendment rights.

"Now, he has hired a high-powered Washington lawyer and has yet to apologize," she said. "He is putting more effort into self-preservation than serving his constituents."

There have been regular rallies outside Frelinghuysen's offices that have grown in size over the course of the year. Along with calling on Frelinghuysen to oppose Trump, the protesters want him to hold an in-person town hall meeting, which he has refused to do.

In April, constituents chartered buses to go to Washington to press him to meet. He agreed to hold a series of small-group meetings, but has chosen to hold "telephone town hall" calls with constituents rather than an in-person gathering.

His fundraising report showed that from April through June, he raised $415,000, and had $981,000 in his campaign account on June 30. The $32,000 spent on attorneys during the quarter represents about 18 percent of his total spending during the quarter, which was $176,000.