Newark Mayor Cory Booker asked his inspector general today to investigate how a letter from Barack Obama's presidential campaign got into a four-page program distributed to guests last week at ceremony for the city's African Commission. Booker called the inclusion of Obama's letter a "clear violation of my administration's standards and the ethics legislation my administration wrote in conjunction with Councilman Ronald Rice." The mayor, an honorary co-chairman of Obama's campaign in New Jersey, asked Inspector General James Wright to investigate after The Star-Ledger raised questions about the letter. Booker has asked Wright to prepare a report by Jan. 28 and include recommendations for disciplinary actions The program has also caught the attention of federal authorities, who are looking into whether it violates the Hatch Act, which restricts campaigning in the federal, state and local levels of government. The four-page program was paid for by Newark taxpayers and issued by the city's press information office. It listed a roster of dignitaries scheduled to speak that day about the new commission, which was formed promote policies and awareness of issues concerning Africans and African-Americans in Newark. Obama's letter, bearing his campaign logo, slogan and website appeared on the second page. Mark Alexander, chairman of the Obama campaign in New Jersey, said the candidate wrote a letter of support at the request of the African Commission. He said the campaign never asked to have it placed in the program and that it did not pay for ad space, even though the bottom of Obama's letter carries the disclaimer, "Paid for by Obama for America." "It's what we put on our stationery," Alexander said. "Someone must've photocopied it and put it in the program as is."