All rates, fares, charges, classifications and joint rates and orders establishing rules, regulations, practices or services fixed by the commission shall be in force and shall be deemed prima facie reasonable and valid in any court wherein the reasonableness or validity thereof is properly drawn in question, and the burden shall be upon the party attacking said rates or orders to show that same are invalid or unfair and unreasonable.
Ala. Code § 37-1-99 (1975)