BATON ROUGE, La. — The education department hasn’t followed state-required guidelines for determining whether charter school contracts should be renewed, Louisiana’s legislative auditor said in a report released Monday.

The review by Legislative Auditor Daryl Purpera’s office says the education department relies on its own annual school performance scores, rather than reviewing standardized test score results as required by state law.

School performance scores include more measures than test results for middle schools and high schools.

The audit says that puts the department at risk of renewing charter schools — public schools run by nongovernmental boards free of some restrictions on traditional public schools — that may not have shown the academic improvement required in state law for such renewal.

The Advocate reports the audit says seven of the 18 charter schools it reviewed whose contracts were renewed from the 2011-12 school year through the 2015-16 year didn’t show the gains required in standardized test results. The charter for one high school, auditors wrote, was renewed for three years despite worsening academic performance.

In his response, Superintendent of Education John White disagreed with some of the audit findings.

“Louisiana has a clear and unambiguous history of using students’ improvement on standardized test scores to determine whether to renew charter schools,” White wrote.

The report marks the second time in the past week Purpera’s office has faulted the department’s oversight of charter schools.

When the schools are up for renewal, department officials review their operations and make recommendations to the Board of Elementary and Secondary Education, which has the final say. BESE rules do not spell out how department officials should determine academic performance.

But the audit cites state law that requires “no charter shall be renewed unless the charter renewal applicant can demonstrate, using standardized test scores, improvements in the academic performance of pupils over the term of the charter school’s existence.”