A group of Republican House members sent President Obama a letter Friday asking him to re-sign the Patriot Act extension out of fears the legislation could be challenged in court after the use of a device called an autopen. Just about an hour before the act's expiration date on May 26, President Obama approved the use of an automated signing machine to affix his signature to the bill, while he attended the G8 summit in France.

"Our request is that, out of an abundance of caution, you affix your signature to S. 990 by personally re-signing the enrolled bill. We recall you retaking the Oath of Office on January 21, 2009, over similar concerns for adhering to the Constitution, and believe your signing legislation passed by the United States Congress is of equal importance," reads the letter authored by 21 house members including Reps. Tom Graves and Phil Gingrey of Georgia, Jason Chaffetz of Utah and Allen West of Florida.

The representatives are worried President Obama's use of the autopen could violate Article 1, Section 7 of the United States Constitution which states, "Every bill which shall have passed the House of Representatives and the Senate, shall, before it becomes a Law, be presented to the President of the United States; If he approve he shall sign it, but if not he shall return it..."

The lawmakers also ask President Obama not to use an autopen to sign any further bills passed by Congress.

However, the White House defends the practice, citing a 2005 opinion from the Office of Legal Counsel (OLC) to President George W. Bush which says the constitution would not be violated by using an autopen to sign bills.

Jason Donner is a Fox News Producer based in Washington, D.C. Follow him on Twitter: @jason_donner