Updated

The Justice Department has filed an appeal of a ruling last week that deemed the government's effort to block funding for ACORN unconstitutional.

U.S. District Judge Nina Gershon issued a preliminary injunction against the government last week, saying Congress overstepped its bounds by voting in September to cut off federal funding for the beleaguered community organizing group.

Gershon sided with ACORN's claims that Congress' decision punitively targeted an individual organization, but the Justice Department doesn't agree and seeks to overturn the ruling.

The embattled community organization has been at the center of controversy for months -- first over allegations of voter fraud during the 2008 presidential election and again this year, when a series of undercover videos were released showing some of the group's employees offering advice on how to skirt tax laws and avoid detection by authorities while operating a brothel.

Congress voted to prohibit the provision of federal funds to the group following the revelation.

Republican lawmakers welcomed the news of the Department of Justice's motion.

"Given the numerous ongoing investigations being conducted surrounding ACORN's criminal activities, the federal government will and should vigorously defend what the president signed and Congress overwhelmingly passed -- a bipartisan recognition that ACORN is not fit to receive federal funds to perform duties on behalf of the American people," Rep. Darrell Issa, R-Calif., and a member of the House Judiciary Committee, said in a written statement.

"There is no plausible way we can allow a left-wing activist judge usurp the authority of the president and Congress in an effort to bypass constitutional authority so that a criminal organizations plagued by criminal accusations can have a court-ordered to entitlement to taxpayer dollars," he said.

Rep. Lamar Smith of Texas said the Attorney General Eric Holder's Justice Department has finally "done something right in the ACORN case. Congress has a responsibility and the constitutional authority to prevent taxpayer dollars from being allocated to an organization with a history of criminal conduct."

Issa and Smith, the top Republican on the Judiciary Committee, sent Holder a letter earlier this week urging the department to immediately appeal the ruling.

The two Republican lawmakers are doing their best to make life miserable for ACORN.

In a Dec. 7 letter to Smith and Issa, the Government Accountability Office said it will provide Congress with a report on how ACORN has used taxpayer dollars.

"I am pleased that the GAO has agreed to review ACORN's receipt and use of federal funds," Smith said Thursday in a written statement. "Congress has a responsibility to ensure that no taxpayer dollars are allocated to an organization supporting or engaged in criminal conduct."

But while lauding the GAO's decision, he said ACORN needs to be scrutinized even further.

"The GAO review is a good start, but given ACORN's extensive record of criminal conduct, the FBI must also step in," he said.  "Only an independent criminal investigation conducted by the FBI can get to the bottom of the nationwide allegations against ACORN."