State police yesterday charged Leslie Mollett in the slaying of state police Cpl. Joseph Pokorny. The arrest was announced last night by state police Maj. Frank Monaco at a news conference at county police headquarters in Point Breeze. Maj. Monaco said Mr. Mollett, 30, a recent state prison parolee, would be charged with criminal homicide, theft by taking, resisting arrest, attempting to elude police and firearms violations. Cpl. Pokorny, a 22-year state police veteran, was shot to death early Monday near the Extended StayAmerica hotel in Carnegie.