The Salt Lake Tribune reports 19-year-old Laura Blocker entered the plea Friday in 3rd District Court to the class A misdemeanor.
Judge Judith Atherton suspended a jail sentence and ordered Blocker to complete 24 months of probation and 500 hours of community service.
According to court documents, Blocker's car went out of control, rolled and burst into flames, killing her 19-year-old cousin Kellie McElroy.
Blocker, who escaped with minor injuries, told police she was driving about 100 mph in a 50 mph zone at the time.
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