Elizabeth Smart says she was raped repeatedly each day after she was abducted from her bedroom seven years ago and told she would be killed if she yelled or tried to escape.
Smart testified Thursday morning in U.S. District Court in Salt Lake City as part of a competency proceedings for the man charged in her 2002 kidnapping.
Brian David Mitchell has twice been found incompetent for trial in state court. Mitchell and his estranged wife were found with Smart nine months after she disappeared from her Salt Lake City home.
A judge ruled earlier this week that testimony from Smart, now 21, is relevant to Mitchell's mental competency.
Smart testified that Mitchell was motivated by sex and used religion to get what he wanted.