Seems to be a lot of folks asking lately. This was the contact as of last year. His secretary was extremely helpful when I called.
Sergeant Walter Powers, Jr.
New Orleans Police Department
Special Events Section
Off: 504.658.6201
Fax: 504.658.6240
Cell: 504.421.4571
wpowersnola.gov
They will email you a permit application. You will need to know start time and approximately how many participants. The fee is something like 50 for the application and 300 for the police escort. I paid ours in person 2 days prior to the wedding to avoid any confusion. Hope this helps!