It is the "National Labor Relations Board" that acts as a mediator in disputes between unions and employers, since many people on both sides of the dispute often claim that the other side is acting unjustly, especially when it comes to negotiations.
In Dred Scott v<span>. </span>Sandford<span> the Supreme Court ruled that Americans of African descent, whether free or slave, were not American citizens and could not sue in federal court. The Court also ruled that Congress lacked power to ban slavery in the U.S. territories.
Hope I could help :)
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