The story behind the coin
The US Marshals Service is the oldest federal law enforcement agency in the country — older than the FBI, older than the country's modern borders, older than almost everything we think of as "the law."
It was born on September 24, 1789, in the same Judiciary Act that built the federal courts. George Washington appointed the first marshals — one for each of the original federal judicial districts — and handed them a job that was equal parts sheriff, bureaucrat, and bodyguard. They served subpoenas, guarded prisoners, paid the courts' bills, and even ran the very first national census in 1790.
In 2014 the Service turned 225. Congress had already cleared the way: on April 2, 2012, President Obama signed the United States Marshals Service 225th Anniversary Commemorative Coin Act — Public Law 112-104 — authorizing a three-coin set to mark the milestone. The half dollar was the affordable, copper-nickel member of that family, sitting alongside a silver dollar and a $5 gold piece. It went on sale in 2015, all of it carrying the dual dates 1789–2014.
A commemorative coin, in the US system, isn't pocket change. Congress has to pass a law to authorize each one, the Mint strikes a limited run for collectors, and a fixed surcharge on every coin goes to a cause named in the law. These coins exist to tell a story and raise money — not to make change at the grocery store.