Final answer:
Shays and his men shut down the courts in Massachusetts to prevent their land from being sold.
Step-by-step explanation:
The reason why Shays and his men shut down the courts in Massachusetts was to prevent their land from being sold. Shays' Rebellion, which occurred in 1786-1787, was a protest against the high taxes and debt faced by farmers in Massachusetts. Many farmers were unable to pay their debts and faced the risk of losing their land through foreclosure. By shutting down the courts, Shays and his followers hoped to prevent the seizure and sale of their property.
Learn more about Shays' Rebellion