TACOMA, Wash. -

A shoplifting incident could send a Tacoma woman to prison for life without parole.

Police say Debra Genia Marzette used pepper spray April 7 on a drug store manager who tried to stop her from leaving without paying for a shopping basket of items, including a package of diapers.

The News Tribune reports she pleaded not guilty Monday to a robbery charge.

Pierce County prosecutors say the 50-year-old could be facing a life sentence because she already has two convictions -- for robbery and burglary -- under the "three strikes" law.