Incredible: While Chicago asks federal government for law enforcement officers, it is sending 50 Chicago police officers to the Democratic Convention in Charlotte

Why are Chicago taxpayers subsidizing the Democratic National Convention?  Why are Federal law enforcement agents being used to subsidize Chicago?  In a sense then the Federal government is subsidizing the Democratic National Convention.  How is any of this reasonable?  You know that something is shady when the Chicago police are ordered not to talk to the press.  From ABC News:

Only days after Chicago Mayor Rahm Emanuel asked for federal agents and U.S. Marshals to help combat the city's wave of violence, about 50 Chicago police officers have arrived in Charlotte to work perimeter security details for a week at the Democratic National Convention.
The Chicago officers, in their distinctive uniforms and checkerboard-brimmed hats, said they had been instructed not to talk with reporters about their out-of-town assignment.
Monday morning some of the Chicago officers were stationed near security screening posts where delegates enter the Charlotte Convention Center. . . . .