William Prescott Jr., graduated from Harvard in 1783, and then taught at Brooklyn, Connecticut, and later at Beverly, Massachusetts.

He passed the bar exam in 1787 after studying law in Beverly with Nathan Dane.

In 1789, he moved his practice to Salem, Massachusetts, where he became a well-known attorney.

He was elected a state senator by the Federal party for Essex County, first in 1806, and again in 1813.

He twice declined a seat on the bench of the Supreme Court of Massachusetts.