Halton Regional Police have charged a 58-year-old Burlington man with sexual assault.William McTaggart is a former instructor at Oxford College in Burlington.McTaggart, who also goes by Bill, was charged with one count of sexual assault and one count of trafficking a drug. His victim is an adult man and a former student.McTaggart was charged following an investigation by the Child Abuse and Sexual Assault Unit.Anyone with information is asked to call Crime Stoppers.