Chadwick Darrin Hunter appeals following the revocation of his supervised release. He argues that the district court erred in admitting and considering various state charging documents that related to conduct which also formed the basis of the Government’s motion to revoke his supervised release.

“A district court may revoke a defendant’s supervised release if it finds by a preponderance of the evidence that a condition of release has been violated.” United States v. Minnitt, 617 F.3d 327, 332 (5th Cir. 2010) (internal quotation marks and citation omitted). In revocation proceedings, we review an assertion of legal error in the admission of evidence de novo, but subject to a harmless error analysis. See id.; United States v. Brigham, 569 F.3d 220, 231 (5th Cir. 2009). “An error is harmless when it does not affect the substantial rights of a party. The government has the burden of establishing harmlessness beyond a reasonable doubt.” United States v. Carrillo, 660 F.3d 914, *332 926 (5th Cir. 2011) (internal quotation marks and citation omitted).

We pretermit a determination whether the district court erred by admitting the charging documents in favor of a determination that the court’s error, if any, was harmless. See, e.g., id. at 929. The charging documents were cumulative evidence of testimony properly given at the revocation hearing. The erroneous introduction of cumulative evidence is harmless error. United States v. Hall, 500 F.3d 489, 444 (5th Cir. 2007). Hunter’s assertion of alleged contradictions between the charging information and the police officer’s testimony at the hearing may not be raised for the first time on appeal. See Leverette v. Louisville Ladder Co., 183 F.3d 339, 342 (5th Cir. 1999).

AFFIRMED.