Dallas ? The Dallas schools superintendent has announced an independent legal review of the district’s investigation into grade-changing allegations for basketball players at South Oak Cliff High.

Superintendent Michael Hinojosa said Wednesday that the district has retained a Houston law firm to review the district’s internal investigation covering the school years that began in 2002, 2004 and 2006.

Earlier this month, Hinojosa told Dallas television station WFAA that the station’s investigations into possible grade changing left him with numerous questions about the district’s internal findings.

WFAA has reported irregularities in the transcripts of several players, including South Oak Cliff graduate and ex-Kansas standout Darrell Arthur, now of the Memphis Grizzlies. The station did not accuse Arthur of any wrongdoing.