The trial court did not abuse its discretion in awarding attorney fees against plaintiff under CCP 2033.420(a) for denying requests for admission denying factual allegations at the heart of the plaintiff’s claims. Plaintiff did not bear his burden of proving that he had reasonable grounds for his denial of those requests for admission. The trial court’s denial of defendant’s non-suit motion did not show plaintiff had reasonable grounds for denial because the non-suit motion was brought on different grounds, and on such a motion, the trial court cannot weigh the evidence.