What law did congress pass to ensure "reasonable and just" railroad rates?

The Interstate Commerce Act of 1887 regulated the railroad industry to avoid its' monopolistic practices. The government did not set specific prices but stated that they needed to be reasonable and just. It prohibited price discrimination which affected mostly small markets. The government required railroads to make public their shipping rates.  It also created the Interstate Commerce Commission which was a federal organization that would monitor railroads.  

the values of the selma marchers was to bring   their ability to vote into law. mlk was not hat march, which was protesting toward lbj