Senate officials recently sent federal law enforcement authorities an additional 2,685 cases of potential violations of the Lobbying Disclosure Act, bringing the total of LDA referrals to 8,281, according to a posting on the Senate's website.

The Office of the U.S. Attorney for the District of Columbia indicates it has not taken enforcement action on any of the potential violations since 2005, except to send letters to potential violators.

The most recent report on LDA compliance efforts was sent by the U.S. Justice Department to key congressional lawmakers last August. It outlines efforts to send letters to potential violators, who were referred by congressional officials for failing to file reports as far back as 2006.

That report said the U.S. Attorney's Office would "assess whether further activity is warranted with respect to referrals ... after there is an opportunity to assess compliance achieved in response to the contact letters."

But the report apparently did not address a large number of recent referrals to DOJ regarding potential violations by individual lobbyists. The vast majority of LDA referrals in 2009 were reportedly for not filing contribution reports known as LD-203 reports.