28 CFR 100.13: Directly assignable costs.
(a) A cost is directly assignable to the CALEA compliance effort if it is a plant cost incurred specifically to meet the requirements of CALEA sections 103 and 104.
(1) A cost which has been incurred for the same purpose, in like circumstances, and which has been included in any allocable cost pool to be assigned to any final cost objective other than the CALEA compliance effort, shall not be assigned to the CALEA compliance effort (or any portion thereof).
(2) Costs identified specifically with the work performed are directly assignable costs to be charged directly to the CALEA compliance effort. All costs specifically identified with other projects, business units, or cost objectives of the carrier shall not be charged to the CALEA compliance effort, directly or indirectly.
(3) The burden of proof shall be upon the carrier to justify that such cost is an assignable cost under this part.
(b) For reasons of practicality, any directly assignable cost may be treated as a directly allocable cost if the accounting treatment is consistently applied within the carrier's accounting system and the application produces substantially the same results as treating the cost as a directly assignable cost.