La. R.S. 47:517

The commissioner, in applying the provisions of this Chapter, has the right to determine in each case whether or not any vehicle is being used or operated, on the public highways of this state in the business of transportation for private gain, as herein contemplated, and if so, whether as a common carrier or as a contract or charter carrier or howsoever, and to that end may, in his discretion, formulate and promulgate reasonable rules and regulations governing such determination and classification.