Louisiana doesn’t license private process servers. In most cases, service is made by the local sheriff’s office, or any private individual appointed by the court.
Licensed private investigators are considered qualified by the courts and do not require any special appointment.
Let’s take a look:
Art. 1293. Service by private person
A. When the sheriff has not made service within ten days after receipt of the process or when a return has been made certifying that the sheriff has been unable to make service, whichever is earlier, on motion of a party the court shall appoint a person over the age of majority, not a party and residing within the state whom the court deems qualified to perform the duties required, to make service of process in the same manner as is required of sheriffs. Service of process made in this manner shall be proved like any other fact in the case. Any person who is a Louisiana licensed private investigator shall be presumed qualified to perform the duties required to make service.
Note: The Louisiana Professional Process Servers Association was active in the state, and maintained a private certification for Louisiana process servers. As of August 2015, their website is no longer accessible.