A complaint against Boeing (BA) filed by the National Labor Relations Board came under sharp attack Thursday by critics who charged that the aerospace giant is being unfairly targeted by pro-union elements of the Obama Administration.

“It’s just another union handout by the Obama Administration, and in this case at the expense of a right-to-work state,” said F. Vincent Vernuccio, labor policy counsel at the Competitive Enterprise Institute, a conservative research center.

The NLRB on Wednesday said Boeing had violated federal labor law when it decided to open a second assembly line for its 787 Dreamliner airplanes in a non-union plant in South Carolina rather than in a union factory near its headquarters outside Seattle.

The complaint alleges that Boeing’s decision was based on the company’s desire to retaliate against the union that represents Boeing workers in Washington, the International Association of Machinists and Aerospace Workers. According to the complaint, that’s a violation of federal labor law.

Boeing said it will go forward with its South Carolina plans while it fights the NLRB complaint.

Boeing spokesman Tim Neale on Thursday said the company had no comment on suggestions that the complaint was political in nature.

In an earlier statement, Boeing’s general counsel, J. Michael Luttig, said: “This claim is legally frivolous and represents a radical departure from both NLRB and Supreme Court precedent. Boeing has every right under both federal law and its collective bargaining agreement to build additional U.S. production capacity outside of the Puget Sound region.”

NLRB spokeswoman Nancy Cleeland responded in an e-mail: “As Acting General Counsel Lafe Solomon made clear in his statement yesterday, this is about the law. The right to strike is guaranteed by the National Labor Relations Act, and employers must stay within the law in making their business decisions.”

Cleeland said the NLRB and Boeing held “extensive discussions with both parties during our investigation and deliberations.”

According to the NLRB complaint, an investigation into Boeing’s actions by the federal agency found that Boeing officials made repeated statements both to the media and its employees in which past worker strikes and the possibility of future strikes were cited as the reason for opening the new production line in a non-union plant.

The NLRB quoted a top Boeing official as telling The Seattle Times, “The overriding factor was not the business climate. And it was not the wages we’re paying today. It was that we cannot afford to have a work stoppage, you know, every three years.”

In a statement, the NLRB said that and similar statements by company executives were “coercive to employees” and “motivated by a desire to retaliate for past strikes and chill future strike activity.” Consequently, Boeing’s actions were illegal, according to the complaint.

Vernuccio questioned that legal logic, arguing that Boeing officials would only have violated federal labor laws if during negotiations they had made promises to employees and then threatened to break those promises unless specific conditions were met.

But that never happened, he said. A threat would have constituted an “unfair bargaining” method, but since there was no threat “there is no merit to the complaint,” said Vernuccio.

Vernuccio said he views the allegations against Boeing as an escalation of the NLRB’s “anti-business” sentiment.

Nevertheless, the labor expert said he was surprised by the complaint. “It came out of left field,” he said.

“Hopefully, this will be fully litigated in a court of law and recognized for what it is – nothing more than political payback without legal precedent – and ultimately tossed out on its head,” Vernuccio said.

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