In a bit of a Senatorial hostage situation, Sen. Chuck Grassley (R-Iowa) is blocking an aide of Sen. Jay Rockefeller’s (D-W.Va.) from a new job on the Federal Communications Commission while Rockefeller is trying to block a Grassley-led investigation into a struggling mobile broadband company.

The dispute is over Grassley’s investigation into LightSquared and the FCC’s initial approval of its plans for a satellite-based mobile Internet network. Grassley has also requested documents from several companies that manufacture GPS devices.

According to Grassley, the two Senators remain personally cordial, but their staffs have battled over jurisdictional issues. As chairman of the Commerce Committee, Rockefeller has jurisdiction over broadcast spectrum. Grassley does not sit on Commerce.

Recently, however, Grassley’s office made an unusual accommodation to the GPS companies in what his office said was an attempt to thwart Rockefeller from tracking his investigation.

The LightSquared-GPS matter is a long-running dispute pitting the Defense Department, a group of Republican lawmakers and the GPS industry against the White House, Federal Communications Commission and LightSquared.

Rockefeller’s office declined to comment for this story, but Grassley’s office offered an account of the ongoing turf war.

Grassley has for months questioned why the FCC initially approved LightSquared’s plan to use satellite spectrum adjacent to that used by GPS devices despite warnings from the GPS makers and the military that the plan could cause interference for GPS devices.

But the FCC has declined to respond to his requests, noting that as ranking member of the Judiciary Committee, he does not have jurisdiction over the commission.

The FCC recently proposed to rescind LightSquared’s approval, and the company has discussed taking the issue to court if that decision is made final. But Grassley is still trying to get to the bottom of how the company obtained approval in the first place.

For leverage, Grassley placed a hold on two of President Barack Obama’s nominees to the FCC, one of whom, Jessica Rosenworcel, is a Rockefeller aide.

Grassley’s demand? That Rockefeller request documents from the FCC on his behalf.

But Rockefeller has refused to ask for the documents from the FCC, and staff-level negotiations in late February resulted in no progress.

Grassley said he hadn’t discussed the matter with Rockefeller personally in months. About the conflict, he said, “It’s nothing personal. He treats me as a gentleman; hopefully I treat him as a gentleman.”

“This is a jurisdictional fight,” said Melanie Sloan, president of Citizens for Responsibility and Ethics in Washington. “Grassley is asking for documents that fall under Rockefeller’s jurisdiction.”

Even though Sloan’s organization fights for increased transparency, Sloan said jurisdictional limits make sense for Congressional investigations. “It could set a difficult precedent … There’d be no end. Companies would have to respond to every Senator. You could spend all your time doing that.”

LightSquared, however, is stuck in the middle and growing increasingly agitated at what it contends is Grassley’s bias toward the GPS industry, which has sought to stop FCC approval of LightSquared’s business plan.

They point to an early March incident in which three GPS companies were permitted by Grassley staff to bring in requested documents for an “in-camera” review, rather than provide copies that Grassley would keep.

LightSquared had struck a deal with Grassley to provide its internal documents if Grassley made a parallel request to the rival GPS companies.

The resulting requests noted the documents were being requested simply pursuant to the deal with LightSquared and not because of allegations about impropriety on the part of the GPS companies.

Even so, Grassley’s office said GPS representatives were livid at meetings about the request, arguing he was attacking the victim of the situation and feeling betrayed by someone they thought was an ally.

Shortly after Grassley publicly requested the documents, Rockefeller sent a request to the same companies requesting copies of whatever documents they provided to Grassley.

Grassley’s office said they object whenever federal agencies or other lawmakers piggyback on the Iowa Republican’s document requests because in some cases the intent is simply to learn what Grassley’s office knows in order to more effectively thwart the investigation.

To thwart Rockefeller, Grassley’s staff arranged for the GPS companies to bring in the documents, review them, and then take the documents out with them ­— an in-camera review that’s unusual for document requests by lawmakers to companies.

The approach voided Rockefeller’s request to the GPS companies because no documents were actually produced to Grassley.

Grassley’s office noted the anger of the GPS companies at the request and said the move is in line with Grassley’s history of opposing such piggybacked document requests. But LightSquared officials are crying foul, calling it one instance in a pattern of Grassley’s partiality to GPS companies in the dispute.

“We have always been concerned about the fairness of this inquiry. This type of accommodation, which was not offered to us, justifies our concerns. This inquiry is meant to protect the GPS industry,” said Lew Phelps, spokesman for Harbinger Capital, which owns a majority stake in LightSquared.

Correction: April 2, 2012



An earlier version of this story incorrectly described the status of LightSquared’s FCC waiver and potential litigation over that decision. FCC has proposed to rescind LightSquared’s waiver and the company has publicly discussed legal remedies if that decision were made final.