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A manufacturing company allows employees to purchase, at cost, manufacturing materials such as metal and lumber, for personal use.  To purchase materials for personal use, an employee must complete a materials requisition form which then must be approved by the employee's immediate supervisor.  The assistant cost accountant then charges the employee an amount based on the manufacturing company's net purchase cost.  

An employee, who happens to be the assistant cost accountant, is in the process of replacing a deck on his home and has requisitioned lumber for personal use, which has been approved in accordance with company policy.  In computing the cost of the lumber, the employee (the assistant cost accountant) reviewed all the purchase invoices for the past year.  The employee then used the lowest price to compute the amount due for the company for the lumber.

Discuss whether this is a good company policy, include if there are proper internal controls in place.  Discuss if the assistant cost accountant behaved in an ethical way.  Discuss if there should be any type of corrective action.  How should the company management handle this situation?  Feel free to share any situations that sound similar in the real world.