Complex sentence: Amelia Robinson met Lyndon LaRouche in 1983, a highly controversial political figure; a year later she served as a founding board member of the LaRouche-affiliated Schiller Institute.
Split into simpler sentences: Amelia Robinson met Lyndon LaRouche in 1983, who is considered a highly controversial political figure. A year later she served as a founding board member of the LaRouche-affiliated Schiller Institute.