Smith said Watts got out of the vehicle and became "noncompliant" and "aggressive," so officers detained him.
On Watts' blog, comments attributed to him Friday denied he had been aggressive and said he had been punched in the face during the arrest. Watts did not immediately respond to an e-mail seeking comment Saturday.
Port Huron police Capt. Jim Jones told the Times Herald that Watts appeared to be angry when officers inspected the black sport utility vehicle that he was driving. Jones told the newspaper that the officers ordered Watts back into the vehicle and when he refused, they tried to handcuff him. He said a scuffle ensued in which Watts choked one of the officers and an officer used pepper spray to subdue him.
Jones did not immediately respond to a message seeking comment Saturday. Port Huron Police said Jones was the only person in the department releasing information on the case.
Smith said the U.S. attorney's office declined to prosecute and that the case was turned over to city police in Port Huron, about 55 miles northeast of Detroit.
Watts was charged with assaulting, obstructing and resisting a police officer, according to St. Clair County District Court records. He was released on a $5,000 bond and is due back in court Dec. 22, the court records said.
If convicted, Watts faces up to two years in prison and a maximum fine of $2,000.
Watts' books include "Starfish," "Maelstrom" and "Behemoth," known as the "Rifters Trilogy."