La. Stat. tit. 17 § 153
The school boards of the several parishes of this state are prohibited from entering into any contract, agreement, understanding or combination, tacitly or expressly, directly or indirectly, with any church, monastic or other order or association of any religious sect or denomination whatsoever, with the representatives thereof or with any person or corporation conducting a school which solicits patronage from those of any particular religious faith, affiliation or persuasion, for the purpose of running any public school or schools of this state together, in connection, or in combination with any private or parochial school, or other institution of learning which may be under the control or management of any church, monastic or other religious order or association of any religious sect or denomination whatsoever, or under the control of any person or corporation conducting a school which solicits patronage especially from those of any particular religious faith, affiliation or persuasion.
La. R.S. § 17:153