Mechanical testing of oil shale from the Parachute Creek Member in Utah's Cowboy Canyon provided the data to evaluate the influence of strain rate and organic composition on the ultimate fracturing strength, the median Young's modulus and the ultimate strain. A multi-parameter statistical analysis demonstrated a strong influence by both organic volume as well as strain rate on the ultimate compressive stresses, while the ultimate strain was influenced by organic volume only. Median Young's modulus showed strong dependency on both organic volume and strain rate. Failure modes ranged from brittle for lean samples at fast strain rates to ductile for rich samples at slow strain rates. A strain rate dependency failure mechanism is proposed to explain the observed behavior. A comparison is made against the behavior of Wyoming's Tipton Member. Mineralogical and geological differences of Tipton and parachute Creek Members on mechanical behavior are elaborated.