RS 47:60

§60. Deductions from gross income; losses by individuals In computing the net income of an individual, deductions shall be allowed for losses sustained during the taxable year and not compensated for by insurance or otherwise: (1) If incurred in trade or business; or (2) If incurred in any transaction entered into for profit, though not connected with the trade or business; or (3) Of property not connected with the trade or business, if the loss arises from fires, storms, shipwrecks, or other casualty or from theft. No loss shall be allowed as a deduction under this subsection if at the time of filing of the return such loss had been claimed as a deduction for estate tax purposes in the estate tax return. The basis for determining the amount of deduction for such losses shall be the adjusted basis provided in R.S. 47:139 for determining the loss from the sale or other disposition of property.