Cato carried the information to Continental Army officers and other revolutionaries, including Alexander Hamilton and George Washington, often crossing the Hudson River into New Jersey.

Because no correspondence with Mulligan's name or a recognized alias on it survives, a complete record of his and Cato's activities during the American Revolution cannot be compiled.

[3] While Cato and Mulligan operated mostly simultaneously with Washington and Benjamin Tallmadge's Culper Ring of American spies, their official affiliation with the group is disputed.

Although historian Alexander Rose has written that Mulligan and Cato began espionage activities within six weeks of Robert Townsend, alias "Samuel Culper, Jr.", sending his first intelligence letter,[4] historian Stephen Knott writes that they began spying in late 1776 or early 1777, well before formation of the Culper Ring in 1778 and mostly independent of it.

Cato carried the message to Washington, who rerouted in such a way to distract the British from the French landing in Newport, Rhode Island.