The present study aimed to characterize what errors in sequential tasks that traumatic brain injury (TBI) subjects make relative to controls. Subjects (8 healthy controls, 6 TBI subjects) completed a computerized grocery bagging task on a touchscreen that required bagging items according to object properties. Relative to controls, TBI subjects produced marginally more errors overall. However, the TBI group had different error profiles than the control group. Specifically, on trials that required a nested rule (i.e. clumping items according to temperature and ordering these same items in terms of weight), the TBI group had more than twice as many errors as controls. This performance deficit is specific to nested rules as the TBI error rates did not differ relative to controls on trials that required multiple rules that were not nested. These findings suggest that planning deficits from TBI cannot simply be due to increased memory load of number of rules but instead is more specific to sequence planning.