WASHINGTON — Michael Steele, who was recently elected chairman of the Republican National Committee, paid a Maryland company run by his sister more than $37,000 for work related to his 2006 Senate campaign, a payment that Mr. Steele’s spokesman said Saturday was entirely appropriate.

The spokesman issued a statement in response to an accusation included in a confidential federal court document that Mr. Steele’s sister had done no work to earn the payment.

Vickie E. LeDuc, a spokeswoman for the United States attorney’s office in Maryland, said Saturday that the office had unintentionally given the document to The Washington Post, which first reported the accusation. Ms. LeDuc would not say if Mr. Steele or his sister was the subject of an investigation.

Mr. Steele did not dispute that his sister’s company, Brown Sugar Unlimited, of Bethesda, Md., had been paid $37,262 by his Senate campaign in February 2007, as federal election records show.