(employee injured because electrical box was still energized when he performed directed work; employee sued independent contractor that installed electrical box; contractor had finished work assigned a week prior to accident and locked up box with special equipment solely in possession of employer; district court granting summary judgment to independent contractor holding contractor had no duty to employee because contractor no longer had control of work site; court of appeals reversed finding the contractor still had control at the time of the incident; upon further review Supreme Court reversed appellate court and affirmed district court's legal conclusion that no duty to employee existed without control of worksite, which contractor had terminated when work was completed; concurrence in part agreeing no duty under Restatement (2d) existed but dissenting in part arguing that duty of independent contractor stems from owing ordinary duty of reasonable care for risks created by contractor's work rather than control over work site as stated by majority opinion).