By BEN NUCKOLSAssociated Press WASHINGTON (AP) – A second former aide to District of Columbia Mayor Vincent Gray was charged Wednesday with a federal offense arising from Gray's 2010 campaign and intends to plead guilty, a day after another aide's guilty plea revealed the use of underhanded tactics to get Gray elected. Howard Brooks, a 64-year-old campaign consultant to Gray, faces a single count of making a false statement to the FBI. He was charged in a criminal information, a document that typically means a defendant has reached a plea deal. A plea hearing was scheduled for Thursday afternoon in U.S. District Court. According to the document, Brooks told FBI agents in April 2011 that he never gave any cash, money orders or other payments to the campaign of minor mayoral candidate Sulaimon Brown, when in fact Brooks did make such payments. At some point after the agents interviewed him, Brooks began cooperating with the FBI. The charges have rattled the first-term mayor, who has been the subject of a federal probe since Brown went public last March with allegations that he was paid by the Gray campaign and promised a job in the Gray administration in exchange for making disparaging comments about then-mayor Adrian Fenty on the campaign trail. Gray has denied knowledge of the payments. Gray declined to comment Wednesday on the charges, citing the ongoing investigation. “We'll let the investigation play out as well as it should, and then we'll see where we are,” Gray said before chastising reporters for not paying attention to “the good things that are going on in this city.” Gray won the 2010 Democratic primary by 10 percentage points after tapping into widespread dissatisfaction with Fenty, perceived by many as aloof. Gray, 69, billed himself as the more ethical candidate, criticizing Fenty for steering lucrative government contracts to his fraternity brothers. But Gray's administration has been mired in scandal since shortly after he took office. Thomas Gore, the acting treasurer for Gray's campaign who pleaded guilty Tuesday, said in court that he was captured on a wiretap talking to Brooks about shredding evidence of payments to Brown. Brooks was not mentioned by name in court because he had not yet been charged. Gore acknowledged at his plea hearing that he and Brooks conspired to convert undocumented cash contributions into money orders that were given to Brown, and that Brown was paid to stay in the race and disparage Fenty. The money orders contained the names of relatives and associates of Brooks, including his son Peyton Brooks. Gore admitted giving Brown $660 in money orders, although Brown contends the Gray campaign gave him more. Peyton Brooks' attorney, Troy W. Poole, confirmed Wednesday that his client has been granted immunity from prosecution in the ongoing federal probe. Poole added that Howard Brooks' guilty plea had nothing to do with his client receiving immunity. The charge against Brooks is a felony that carries a maximum penalty of five years in prison, although Brooks would likely receive a much lighter sentence under federal guidelines. His cooperation also could lead to a reduced sentence. Brooks' attorney, Glenn Ivey, did not return a message seeking comment. Brooks and the mayor are not close – Gray said in late 2011 that he had not spoken to Brooks all year – and Brooks is not well-known in district politics. He is, however, a close personal friend of Lorraine Green, Gray's campaign chairwoman and closest adviser during his 2010 bid. Brown has said he also received money from Green before she delegated that task to Brooks. Brooks was rewarded handsomely for his work on the Gray campaign, receiving $44,000 in consulting fees. He was also paid $34,500 by the Gray transition. Council Chairman Kwame Brown is also the subject of a federal probe for actions during his 2008 campaign, and former councilmember Harry Thomas Jr. is heading to prison after pleading guilty in January to embezzling from the city. Several Gray campaign staffers have said Sulaimon Brown's harsh rhetoric against Fenty at campaign forums amounted to a sideshow that did nothing to help Gray, although Brown has claimed his efforts were crucial. The Gray administration appointed Brown to a $110,000-a-year position in January 2011 and fired him less than a month later. In a statement emailed to reporters Wednesday morning before the charges against Brooks were filed, Brown called on Gray to resign for violating the public trust. He also praised U.S. Attorney Ronald Machen for his efforts. “I was not looking for vindication for the truth need not be vindicated,” Brown wrote. “I was seeking justice.” ___ Associated Press writer Eric Tucker contributed to this report. ___ Follow Ben Nuckols on Twitter at twitter.com/APBenNuckols. Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.