[cnn-photo-caption image= http://i.cdn.turner.com/cnn/2008/images/04/16/art.reid0416.ap.jpg caption="The Senate, led by Democrat Harry Reid, is expected to vote soon on a request to investigate a Florida earmark."]
WASHINGTON (CNN) - The Senate may seek a federal investigation into a 2005 earmark on a highway funding bill that was mysteriously altered after Congress approved the measure but before President Bush signed it.
The $10 million earmark, originally designated for improvements to Interstate 75 in Lee and Collier Counties in Florida, was changed to direct the money to build an interchange in Lee County, an apparent violation of congressional rules.
"This wasn't an ordinary earmark," Sen. Charles Schumer, D-New York, said, defending the decision by Democratic leaders to invite the Justice Department to probe internal congressional practices. "It was the specific circumstances here that are highly unusual."
The Senate is expected to vote Thursday whether to direct the Justice Department to investigate "allegations of impropriety" and to "ascertain if a violation of Federal criminal law has occurred." No lawmaker has acknowledged making the change.
"If there's something untoward done, whether it's morally wrong, criminally wrong, let's take a look at it," argued Senate Majority Leader Harry Reid, D-Nevada.
Rep. Don Young, R-Alaska, who was then the chairman of the transportation committee and chief author of the bill, says he asked for the initial project money during the 2005 congressional session for "widening and improvements for I-75 in Collier and Lee counties."
But before the bill got to the President's desk for his signature, the wording of the earmark was changed and the $10 million was redirected to build the "Coconut Road interchange I-75, Lee County."
Democrats widely believe Young directed someone to change the language. They note that as the bill was moving through Congress, Young received $40,000 in campaign contributions from local business leaders who stood to gain from a new highway interchange at that location.
In a brief exchange with CNN as he left the House floor Wednesday, Young repeatedly said "no comment" when asked if he had anything to do with the change to the earmark.
It was unclear if the Justice Department would be bound by a Senate vote to seek an investigation. Democratic lawmakers argued that the department would be required to launch the investigation, but Sen. Tom Coburn, R-Oklahoma, argued that the department would not necessarily have to launch the probe.
Coburn, who champions reforming the earmark process, is pressing for a special congressional committee to investigate the matter. But Democratic leaders oppose the idea because they say it would be unconstitutional for senators to investigate members of the House.