Rep. Justin Amash, R-Mich., one of the few congressmen who has been labeled "libertarian," has introduced an amendment to the defense appropriations bill that would defund the National Security Agency.

Amash announced his push to defund the NSA on his Twitter account, writing "Most important bill this week: DoD Approps. We can defund NSA's unconstitutional spying on Americans — if House leaders allow amendments."

The last part of that tweet refers to the sudden decision by the House Rules Committee to limit the number of amendments that can be included in the bill. "While this is not the traditional process for this bill," Rep. Pete Sessions, R-Texas, wrote in a letter to lawmakers, "there are a number of sensitive and ongoing issues related to national security that are more appropriately handled through an orderly amendment process ensuring timely consideration of this important measure."

Prior to Republicans taking over the House in 2011, important bills and appropriations bills were not always given an open amendment process. House Speaker John Boehner, R-Ohio, promised that would change. The reason the amendment process may be closed for this year's defense bill is because of fears that controversial amendments on NSA, Egypt or Syria will be brought to the floor.

"They're concerned about attempts to defund the NSA spying programs or tie the president's hands in Syria and now Egypt as well," an unnamed defense industry source told The Hill last week.

The NSA's controversial data collection efforts have come under fire since whistleblower Edward Snowden leaked information that the agency monitors telephone, email and other communications of Americans regardless whether there are any indications they are linked to terrorists. Amash's amendment may not even get a vote, but it's one more reason the NSA spying scandal stays in the public eye.