Conversation so far:
When did Kenesaw Mountain Landis become a judge?
As an acting Federal Judge from 1905-1922.
What position did Kenesaw Mountain Landis hold when he became a judge in 1905?
He was the judge of the United States District Court for the Northern District of Illinois.
Where was Kenesaw Mountain Landis a judge?
Landis's courtroom, room 627 was in the Chicago Federal Building.
Did Kenesaw Mountain Landis work in baseball?
Landis was selected in 1920 to become the first Commissioner of Major League Baseball.
What did Kenesaw Mountain Landis do during these years?
He is remembered for handling the Black Sox scandal, in which he expelled eight Chicago White Sox members from organized baseball for conspiring to lose the 1919 World Series
Did Kenesaw Mountain Landis have any other notable cases besdies the Black Sox scandal?
In 1915, the upstart league brought suit against the existing leagues and owners under the Sherman Act and the case was assigned to Landis.
Were there any other big cases besides the Black Sox scandal and the Federal League?
On April 1, 1918, Landis presided over a trial against 113 defendants, IWW leaders, including union head Big Bill Haywood, the largest federal criminal trial to that point.
What else did Kenesaw Mountain Landis do during this time as Jude of the United States District Court for the Northern district of Illinois?
Landis struck down a challenge to the Interstate Commerce Commission's (ICC) jurisdiction over rebating. Landis's decision allowed the ICC to take action against railroads which gave rebates.

Question: What did the railroads do?
Self-contained rewrite: What did the railroads do which caused the ICC to take action over giving rebates?