It is the case that the government simply will not let die.

Three years ago, the Justice Department dropped espionage-related charges against Sherry Chen, a Chinese-American hydrologist at the National Weather Service, clearing her of accusations that she had used a stolen password to download information about the nation’s dams and lied about a meeting with a high-ranking Chinese official.

But Ms. Chen still can’t get back to work. Even though her name was cleared, her employers at the Commerce Department — which oversees the National Weather Service — continue to press their case that Ms. Chen be fired for many of the same charges she was exonerated of, according to two people familiar with the case but not authorized to speak about it publicly.

The Commerce Department said it planned to fire Ms. Chen in 2015. She appealed to the federal Merit Systems Protection Board, an independent, bipartisan board charged with safeguarding the rights of civil servants. Last month — in an unusually strong-worded statement — the board ruled that the Commerce Department must reinstate her, give her back pay and cover her legal fees.

In the ruling, the judge overseeing the case, Michele Szary Schroeder, suggested that Commerce officials had buried exculpatory evidence that would have cleared Ms. Chen. She also wrote that the two officials who had decided to fire Ms. Chen appeared “more concerned about being right than doing the right thing.”