Witness25/04/2015BBC News Channel Duration: 30 minutesFirst broadcast: Sat 25th Apr 2015, 00:30 on BBC News ChannelLatest broadcast: Sun 26th Apr 2015, 16:30 on BBC News Channel HDThe father of a Nascar driver killed in an accident tells Witness about how his death changed the safety rules of the sport.GenresFactualArts, Culture & the MediaBrandWitness Source: BBC Online