Red Rock Resorts has lost a federal court bid to halt sprawling labor proceedings stemming from years of allegations the operator illegally sought to undermine unions at their Las Vegas properties.

U.S. District Judge Anne Traum last week dismissed a lawsuit brought by Red Rock Resorts, its Station Casinos brand, and numerous affiliated casino entities that challenged the constitutionality of the National Labor Relations Board (NLRB).

The lawsuit was an attempt to stop two ongoing NLRB proceedings involving allegations of unfair labor practices across the Station Casinos group.

Rather than addressing those allegations in the suit, Red Rock argued that aspects of the NLRB itself were unconstitutional. Among other things, it claimed federal law makes it too difficult for the US president to remove NLRB board members and administrative judges, improperly limiting presidential authority.

Red Rock also argued the agency exercises an unconstitutional combination of powers because it can investigate and prosecute alleged labor violations while also playing a role in deciding those disputes.

Traum rejected the claims, finding Red Rock had failed to show that the NLRB’s structure had actually caused it harm. The judge noted that even if restrictions on removing NLRB officials were unconstitutional, that would not automatically invalidate decisions made by officials who were legally appointed.

The case was dismissed without prejudice, meaning Red Rock has an opportunity to amend its complaint and try again.

Station Casinos’ battle with organized labor in Las Vegas dates back to 2018, when the NLRB launched the first of many proceedings arising from unfair-labor-practice complaints.