President Trump’s older sister, Maryanne Trump Barry, has retired as a federal appellate judge, ending an investigation into whether she violated judicial conduct rules by participating in fraudulent tax schemes with her siblings.

The court inquiry stemmed from complaints filed last October, after an investigation by The New York Times found that the Trumps had engaged in dubious tax schemes during the 1990s, including instances of outright fraud, that greatly increased the inherited wealth of Mr. Trump and his siblings. Judge Barry not only benefited financially from most of those tax schemes, The Times found; she was also in a position to influence the actions taken by her family.

Judge Barry, now 82, has not heard cases in more than two years but was still listed as an inactive senior judge, one step short of full retirement. In a letter dated Feb. 1, a court official notified the four individuals who had filed the complaints that the investigation was “receiving the full attention” of a judicial conduct council. Ten days later, Judge Barry filed her retirement papers.

The status change rendered the investigation moot, since retired judges are not subject to the conduct rules. The people who filed the complaints were notified last week that the matter had been dropped without a finding on the merits of the allegations. The decision has not yet been made public, but copies were provided to The Times by two of the complainants. Both are involved in the legal profession.