As Jackson Health System has struggled to pull out of a daunting financial hole for the last two years, a member of the board that oversees the system has been accused of abusive behavior toward employees in the collections office as he tried to negotiate settlements for unpaid bills owed by his law firm’s clients, according to ethics complaints filed by two Jackson administrators.

The allegations against Stephen Nuell, a Miami personal injury attorney and member of the Financial Recovery Board appointed to help turn around the troubled system, are detailed in complaints filed by the director and the associate administrator of the hospital’s business office.

They allege that Nuell repeatedly called the business office between May 2011 — when he was appointed to the board — and October 2012 to resolve matters for private clients despite being told specifically not to do so.

The two employees also accused Nuell of screaming at them over the phone, calling them “incompetents” and contacting hospital executives directly to intervene when he was unhappy with their efforts.

Nuell declined to comment on the allegations that he exploited his position on the hospital’s board for personal gain.

“There’s a confidential investigation going on,’’ he said.

Edwin O’Dell, a Jackson spokesman, said hospital executives and employees familiar with the complaints against Nuell would not comment.

“We don’t want to damage the investigation,’’ he said.

The complaints against Nuell were filed in October with Miami-Dade’s Commission on Ethics and Public Trust, which is investigating the allegations. It is unclear from the documents whom Nuell was representing in the settlement negotiations.

Joseph Centorino, executive director of the ethics commission, said the complaints and investigation are confidential. He declined to comment on Nuell’s case.

But copies of the employees’ complaints were made available to the Herald, along with a February 2013 memo from the commission’s deputy general counsel recommending a finding of probable cause that Nuell violated Miami-Dade’s Conflict of Interest and Code of Ethics ordinance.

The complaints against Nuell were notarized, and signed by JaNene Church, director of the hospital’s corporate business office, and Norma Linares, associate administrator. Employees in the business office collect outstanding patient bills and negotiate settlements with personal injury attorneys.

Church and Linares did not reply to repeated requests for comment. But the memo from the ethics commission attorney indicates there is merit to their complaints, which are very similar.

Miriam Soler Ramos, deputy general counsel for the ethics commission, wrote in a memo dated Feb. 13 that she believes Nuell violated three sections of the county’s ethics ordinance, which prohibits hospital board members from appearing before any county agency on behalf of a third person — and then receiving payment from that party. The Financial Recovery Board has been temporarily handling Jackson during the financial crisis but the board will revert to its previous name, the Public Health Trust, in May.

The ethics ordinance also bars hospital board members from participating in settlement negotiations of claims or lawsuits involving the hospital without prior approval from the governing board, which Nuell did not have.