Complex sentence: His office is currently investigating an alleged conspiracy to sell Barack Obama's vacated U.S. Senate seat to the highest bidder which led to the arrest of Illinois Governor Rod Blagojevich on December 9,2008.
Split into simpler sentences: His office is currently investigating an alleged conspiracy to sell Barack Obama's vacated U.S. Senate seat to the highest bidder. This led to the arrest of Illinois Governor Rod Blagojevich on December 9,2008.