[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2010/images/03/26/art.okeefe.jpg caption="Conservative activist James O'Keefe is one of four men now charged with a misdemeanor for entering Sen. Mary Landrieu's office in Louisiana."]
Washington (CNN) - Prosecutors have reduced the charges against four men accused of trying to access the phone system in the New Orleans office of Sen. Mary Landrieu, D-Louisiana.
The case involves James O'Keefe, the conservative activist who played a pimp in videos that later embarassed ACORN, the community organizing group now in the process of shuttering its operations. The case also involves Robert Flanagan, the son of an acting U.S. attorney from Louisiana's Western District.
The U.S. Attorney's office for the Eastern District of Louisiana said Friday that O'Keefe, Flanagan and the two other associates are now charged with entering federal property under false pretenses, a misdemeanor.
The men were originally arrested on felony charges after they entered Landrieu's office, located inside a federal building, on Jan. 25.
Days before, according to a Bill of Information released by the Justice Department, the four men plotted ways to talk with members of Landrieu's staff inside her office, "and record the interaction using audio and visual equipment."
The statement adds that two of the men entered the senator's office dressed as telephone repairmen, told staffers they needed to work on the phone system, and pretended to test it. O'Keefe also entered the senator's office and recorded the interaction.
The office of Flanagan's lawyer, J. Garrison Jordan, said Jordan was out of the office. Attempts to reach lawyers for the other defendants were unsuccessful.
In a statement to CNN, Sen. Landrieu said, "It is clear that these four men deliberately deceived both building security and my staff by using phony identities to gain access to a federal building. Clearly they were up to no good."
Landrieu called the men's alleged actions "a blatant violation of the law that carries with it serious consequences."
O'Keefe has previously said he is not a criminal but an investigative journalist.
If convicted, O'Keefe and the three other men could each face a maximum sentence of six months in prison and a fine of $5,000, according to the Justice Department statement.
Editor’s note: The original story has been updated to reflect new language in the first sentence. The words “tamper with” have been struck and replaced with “access” to accurately describe the charges. The new sentence now reads: Washington (CNN) – Prosecutors have reduced the charges against four men accused of trying to access the phone system in the New Orleans office of Sen. Mary Landrieu, D-Louisiana.