Translation:The journalist checks corruption in Congress.
The United States Congress is usually simply referred to as Congress. Outside of 18th century writings, it is almost NEVER referred to as "the Congress". The term "the congress" refers instead to a particular meeting of a professional society, like the International Congress of Mathematicians.
Meanwhile, the phrase "checks corruption" doesn't really make sense, at least not in American English. A journalist might check ON the corruption in Congress (which DL rejects), but he wouldn't check the corruption.