Mikel Hilerio, 29, is accused of throwing his girlfriend's twins into the water at Constitution Beach.
Bystanders called 911 and filmed the incident on Monday.
His defense attorney says that the children do suffer from Autism and tend to act out. He believes his client was just playing.
Prosecutors also allege that he may have been under the influence of heroin at the time of the incident.
It is still under investigation by The Department of Children and Families, the children were evaluated at a local hospital.