Gary Hardy challenges a declaratory judgment, denying benefits under a commercial automobile policy issued by Pharmacists Mutual Insurance Company (PMIC).

In September 2003, Hardy’s son was killed in an automobile accident in Boone-ville, Mississippi while driving Hardy’s vehicle. Hardy seeks $250,000 in under-insured motor vehicle benefits under a commercial automobile policy, issued by PMIC. Following a September 2005 bench trial, the district court entered a declaratory judgment in favor of PMIC.

Because federal jurisdiction is premised on diversity grounds, we apply Mississippi substantive law. See Erie R. Co. v. Tompkins, 304 U.S. 64, 58 S.Ct. 817, 82 L.Ed. 1188 (1938). In addition, “[t]he standard of review for a bench trial is well established: findings of fact are reviewed for clear error and legal issues are reviewed de novo ”. In re Midr-South Towing, Co., 418 F.3d 526, 531 (5th Cir. 2005) (internal citation and quotation marks omitted). Interpretation of an insurance policy is a question of law, reviewed de novo. Allstate Ins. Co. v. Disability Serv. of the Southwest, Inc., 400 F.3d 260, 263 (5th Cir. 2005).

The district court ruled: Hardy’s vehicle, operated by the decedent at the time of the accident, was not a covered vehicle under the PMIC commercial policy; instead, it was insured under a personal insurance policy issued by a different insurer. Accordingly, it concluded: because the decedent was not operating a covered vehicle at the time of the accident, there could be no recovery under PMIC’s policy. See Crane v. Liberty Mut. Ins. Co., 19 F.Supp.2d 654, 659 (S.D.Miss. 1998) (“covered vehicle” is a “vehicle insured under *365 the liability provisions of the subject policy”.); see also Miss.Code Ann. § 83-11-103(b) (1999). This conclusion, not challenged by Hardy, is dispositive of this appeal. (Hardy disputes the district court’s ruling concerning other reasons the decedent was not an “insured” under the terms of the PMIC policy. Because the district court did not err in its not-covered-vehicle ruling, we need not reach this issue.)

AFFIRMED.