Miss. Code Ann. § 65-21-15

The board of supervisors of one or more counties, acting individually or jointly by agreement with the private owner or owners, may purchase and maintain toll-free one or more toll bridges in one or more counties. However, this section and 65-21-17 shall not apply to any interstate bridge, nor the bridge across the Pascagoula River at Pascagoula, Mississippi, nor to any bridge on any designated state highway maintained in whole or in part by the state highway department.