[2] As mayor, Watson had the duty of organizing Philadelphia's reception for the Marquis de Lafayette on his tour of the United States.

Both were southern plantation owners who had been approached by Jesse Cannon and Joe Johnson of the Cannon-Johnson Gang to buy Sam Scomp and Enos Tilghman.

Watson worked to obtain affidavits from family and employers and the Pennsylvania Abolition Society joined to find documentation that the teenagers were indeed free.

In the case of Scomp and Tilghman, Watson reached out to Richard Stockton, who was the Attorney General of Mississippi.

Stockton was opposed to kidnapping free blacks, and informed Watson it was a matter of going to the Circuit Court with evidence.

He issued a proclamation offering a reward of 500 dollars for the apprehension and prosecution of anyone involved in kidnapping free blacks in the city.

Watson assigned his constable Samuel Garrigues, who had helped free the kidnapped slaves, to set out to arrest members of the Cannon Gang.