The answer to your question is "The Civil Service Act"
Explanation:
This quote from Gilded Age Politics:Crash Course US History #26:
"Despite that and the widespread corruption, some national reform legislation actually did get passed in the Gilded Age. The Civil Service Act of 1883, prompted by Garfield's assassination by a disgruntled office-seeker, created a merit system for 10% of federal employees, who were chosen by competitive examination, rather than political favoritism."
