Why was the Supreme Court’s decision in the Wabash, St. Louis, and Pacific Railroad v. Illinois case an obstacle to state government reform measures?

In Wabash, St. Louis, and Pacific Railroad v. Illinois (1886), the Supreme Court ruled that a state could not regulate railroad rates for traffic crossing state lines. Regulation of interstate commerce was a power of the federal government, so states could not use their reform laws to control interstate railroads. The correct choice is “The Supreme Court ruled that states cannot regulate interstate railroads.”

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