Former Trump campaign aide Michael Caputo said “it would be a real blessing” if the fund were able to assist with the legal costs that he and others face. (Chip Somodevilla/Getty Images)

A new legal defense fund designed to help defray the costs faced by aides to President Trump drawn into the various Russia investigations has yet to answer key questions regarding how it will vet donors and provide transparency about the contributors who finance the effort.

The Patriot Legal Expense Fund Trust filed paperwork Tuesday with the Internal Revenue Service and the Delaware secretary of state, declaring it will operate as a political committee and help defray the legal costs of “eligible persons” involved in the investigations.

The trust plans to allow both individuals and “entities” to make unlimited donations that will be pooled to defray the costs of multiple recipients, according to paperwork filed in January with the Office of Government Ethics.

But the filings offered little insight into how the fund will operate, raising concerns about its transparency and how it will comply with conflict of interest rules, ethics experts said.

Attorneys from the Washington-based law firm Wiley Rein, who established the fund, declined to comment. The White House did not respond to requests for comment. A news release announcing the launch of the trust offered few details, and a spokesman and the interim manager for the fund did not immediately respond to requests for comment.

Questions about how the fund will raise and distribute money are building amid signs that special counsel Robert S. Mueller III’s investigation is intensifying.

According to figures released last month by the White House, at least 48 White House staff, campaign staff and others affiliated with the campaign have voluntarily given interviews to the special counsel or congressional committees.

Trump associates pulled into the inquiries said they are contending with growing legal costs.

Michael Caputo, a former Trump campaign aide who has been interviewed by the House Intelligence Committee and contacted for two interviews by two Senate committees, estimates his legal bills will range from $75,000 to $125,000.

“There are dozens of people in this situation, some of them much worse than me,” said Caputo, who added that he has spoken with numerous aides worried about their legal bills.

“Everyone is talking about it privately,” he said. “If this Patriot Fund is real and they can help any one of us pay our legal bills, it would be a real blessing.”

One reason for the delay in the fund’s launch has been a search for an administrator to manage the trust, according to an official familiar with the planning.

Former congresswoman Nan Hayworth (R-N.Y.), who supported Trump in the 2016 campaign, was named interim manager of the fund Tuesday while the search for a permanent manager continues, according to the news release.

The trust’s manager has broad authority to decide who gets reimbursed and how much, filings show.

Those who could be eligible to receive money through the fund include employees, consultants or volunteers in the Trump campaign, transition and administration who have been involved in the investigations, according to the statement from the trust.

Ty Cobb, the attorney handling the White House’s response to the Russia investigators, said in November that those who were targeted or indicted in the investigation would not qualify to receive financial help from the legal fund. Tuesday’s news release specified that legal expenses incurred “on behalf of any party which arise from the defense of any charge or indictment for dishonest, fraudulent or criminal activity” would not be reimbursed through the fund.

In deciding which aides to reimburse, the fund’s manager cannot consider whether an aide’s involvement in the investigation is favorable to Trump, according to the draft agreement.

Unlike the two legal defense funds established to assist President Bill Clinton and first lady Hillary Clinton in the 1990s, the Patriot Fund will pool money from a variety of donors and entities for an undetermined number of recipients. The two Clinton funds were established to defray the couple’s legal expenses and were not available to their aides, documents establishing the funds show.

The Patriot Fund will include at least two separate accounts — one for federal employees and one for nonemployees — in an effort to avoid potential conflicts of interest posed by donors. But experts say the distinction between the accounts could get lost without careful tracking and vetting.

“The question is: Does one bad apple spoil the whole pot for everybody involved?” said Marilyn L. Glynn, a former Office of Government Ethics general counsel who helped shape disclosure and contribution requirements for the Clinton funds.

The fund’s filings indicate that donors will be responsible for flagging any potential conflicts by filling out a questionnaire that asks them about foreign lobbying and federal contracts, among other issues.

Under IRS guidelines, the fund will be required to disclose donors who give $200 or more monthly or quarterly in an even year, which would mean its first disclosure would probably be filed in mid-April. Officials have not yet said how often they plan to disclose the names of contributors.

Donations to legal defense funds for public officials usually are capped at a certain amount. Members of Congress have donation limits set through congressional rules — $5,000 annually per source for the House and $10,000 for the Senate, according to research by Ellen Aprill, a tax law expert at Loyola Law School in Los Angeles. Donations to the Clintons’ legal fund were voluntarily capped at $1,000 for the first fund and $10,000 for the second, according to Aprill.

But the Patriot Fund’s filings do not address whether there will be any limits on how much each contributor can give.

Even though the fund said it will not accept anonymous contributions, it will take donations from entities — which could include limited liability companies, according to experts who reviewed the Office of Government Ethics filing. Donations given through LLCs can often mask the identity of the contributors.

“This is strikingly different from either of the Clinton legal defense funds,” said Kathleen Clark, legal and government ethics professor at Washington University School of Law. “The bottom line is: There is an astounding level of secrecy.”

The Office of Government Ethics last month reviewed the fund’s draft agreement and found that it complied with federal rules. The office said it “does not approve or disapprove of specific legal defense funds.”

Alice Crites and Carol D. Leonnig contributed to this report.