Ex Parte Myra Clarke Whitney was a case heard before the United States Supreme Court in 1839. The petitioner, Myra Clarke Whitney, sought to be released from her husband's guardianship and have control of her own estate. She argued that she had been married at an age when she could not legally consent to the marriage contract and therefore it should be voided. The court ruled against her on the grounds that there was no legal precedent for voiding a marriage contract due to lack of consent by one party. However, they did recognize that if such a law were passed in future cases then this would provide relief for those who are unable to give their full consent due to their young age or other factors beyond their control. This ruling set an important precedent regarding marital contracts and established guidelines for determining whether or not someone is able to legally enter into such agreements.

In Ex Parte Myra Clarke Whitney, the Supreme Court was asked to determine whether a writ of habeas corpus should be issued in order for an enslaved woman to gain her freedom. The majority opinion held that since slavery is not recognized by the Constitution and laws of the United States, it could not issue such a writ. However, Justice McLean dissented from this decision on two grounds: firstly, he argued that Congress had exclusive power over slavery and as such they were able to pass legislation which would grant relief; secondly, he argued that even if Congress did not have authority over slavery then state law still allowed for slaves who had been illegally brought into free states or territories to obtain their freedom through habeas corpus proceedings. He concluded his dissent by stating that “the court has no right to deny justice when applied for in proper form” and thus urged them to reconsider their decision.