WASHINGTON — A man suing the Secret Service for discrimination has sent racially offensive e-mails, according to new evidence filed in court.

The court documents include e-mails sent by plaintiff Reginald Moore, who is black, containing a joke about a black woman hitting her daughter and a picture of a wedding reception at a White Castle hamburger restaurant. The Secret Service declined to talk about the recent filings.

This is the latest twist in an 8-year-old racial discrimination case against the Secret Service. A group of black employees say the agency has passed over black agents for promotion. They say white colleagues and supervisors regularly use a racial epithet to refer to criminal suspects and black leaders of other countries. The lawsuit claims the Secret Service has always had a discriminatory culture — a claim the agency has consistently denied.

Last month an employee found a noose in one of the Secret Service's training centers. A worker who tied the noose out of canine training rope has since been placed on administrative leave, according to the agency.

As part of the discrimination lawsuit, the Secret Service was ordered to turn over evidence. The agency paid an outside auditor more than $2 million to search 20 million e-mails and other electronic documents dating back 16 years.

Among the 10 e-mails submitted to the court earlier this month in a separate filing were jokes circulated within the agency that referred to: the way a "20-year-old 5th grader" in Harlem spoke; an assassination of the Rev. Jesse Jackson; and the work ethic of a black golf caddy.

One of the e-mails was sent by a deputy assistant director, who has since been suspended. In addition, one of the supervisors who sent an e-mail was on Sen. Barack Obama's security detail for the past year. The supervisor is no longer on the security detail and has been promoted to a position at the agency's Washington headquarters.

The lawsuit was filed in the U.S. District Court in Washington in 2000. Lawyers say the Secret Service has delayed turning over evidence in the case. They are scheduled to argue that issue in court Thursday.

In 2007, 80 percent of the people who worked at the Secret Service were white, and 10 percent were black, according to data obtained by The Associated Press. The remaining 10 percent were of other races. In the agency's senior leadership, whites made up about 75 percent and blacks 13 percent. Blacks make up about 12 percent of the United States' population.

The Secret Service investigates counterfeiting cases and protects presidents, vice presidents, their family members and other dignitaries. The agency, previously part of the Treasury Department, became part of the Homeland Security Department in 2002.