An adult son of Rep. Katherine Clark was arrested during a protest on Saturday, January 21, 2023, on Boston Common and later charged with assault after a police officer was injured. | Mariam Zuhaib/AP Photo BOSTON — The daughter of House Democratic Leader Katherine Clark has been charged with assault after an altercation with a police officer who was trying to arrest her for allegedly spray-painting anti-police messages on the bandstand on Boston Common. . Riley Dowell, 23, who was identified in a police press release On Sunday under the name Jared, which Clark's office identified as his former name,…