(Reuters) - A U.S. appeals court on Friday said the National Labor Relations Board had "miserably failed" to explain why it declined to retroactively apply a Trump-era ruling allowing companies to cease bargaining with unions that are rejected by a majority of their members to a case involving a furniture manufacturer.

A panel of the U.S. Court of Appeals for the D.C. Circuit said the NLRB had effectively penalized Leggett & Platt Inc for exercising its appellate rights by not applying a standard the board adopted in the 2019 case Johnson Controls Inc to the company's case after an earlier trip to the appeals court.

The board in Johnson Controls said employers can withdraw recognition of unions once a majority of workers in a bargaining unit sign a decertification petition, and unions cannot block the move by later submitting a counter-petition.

Missouri-based Leggett & Platt and its lawyers at Littler Mendelson did not immediately respond to requests for comment.

The National Right to Work Legal Defense Foundation represents Keith Purvis, an employee at the company's Kentucky mattress factory who had pushed to decertify his union. The group's president, Mark Mix, in a statement said the decision was a victory for Leggett employees "who are fighting union bosses' underhanded attempts to trap them in union ranks."

Purvis in late 2016 presented to the plant's management a petition to decertify an International Association of Machinists bargaining unit that had been signed by a majority of its members. The union had represented workers at the factory for more than 50 years.

Leggett in early 2017 withdrew its recognition of the union and informed IAM that it would not engage in bargaining once the collective bargaining agreement in place at the time expired a few weeks later.

IAM launched its own petition drive and ultimately obtained the signatures of a majority of bargaining unit members, including 28 people who had also signed Purvis' petition, according to filings in the case.

The union filed an unfair labor practice complaint against Leggett, claiming that withdrawing recognition without first holding a decertification election violated the National Labor Relations Act.

The NLRB agreed in 2019 but, while Leggett's appeal was pending, decided Johnson Controls, which involved nearly identical facts to Leggett's case and overruled longstanding precedent that said employers cannot withdraw recognition based solely on a petition by workers.

The D.C. Circuit remanded Leggett's case to the board to review it in light of Johnson Controls. But the NLRB last year said that because it had ordered Leggett to bargain with IAM months earlier, retroactively applying the new standard would disrupt the bargaining process.

Leggett again appealed, and the D.C. Circuit on Friday agreed with the company that the NLRB had failed to show how that would lead to a "manifest injustice," which is what the board typically must establish to avoid retroactively applying a new standard.

"The Board has miserably failed to explain how it is a manifest injustice to recognize the party's right of appeal," Circuit Judge David Sentelle wrote.

The panel included Circuit Judges Sri Srinivasan and Neomi Rao.

The case is Leggett & Platt Inc v. NLRB, U.S. Court of Appeals for the D.C. Circuit, No. 20-1060.

For Leggett & Platt: A. John Harper of Littler Mendelson

For the intervenor: Aaron Solem of the National Right to Work Legal Defense Foundation

For the board: Barbara Sheehy