The assassination that led to Congress passing a law on supporting civil service reform was that of James A. Garfield.
James Garfield was assassinated by a man who was tired of not having a job despite having the qualification to do so.
He blamed the patronage system for denying him a fair opportunity and his actions led to Congress supporting civil service reform to prevent such an action from repeating itself.
Find out more on the patronage system at https://brainly.com/question/11512971
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