Employees who cheat on their expense accounts usually do so by one of four methods:

1. Mischaracterized expenses. Employees produce legitimate documentation for nonbusiness-related transactions. Example: taking a friend to dinner and charging it to the company as "business development."

2. Overstated expense reports. Employees inflate the amount of actual expenses and keep the difference. Example: altering a taxicab receipt from $10 to $40.

3. Fictitious expenses. Employees submit phony documentation for reimbursement. Example: producing a fake hotel bill on a home computer.

4. Multiple reimbursements. Employees copy invoices and resubmit them for payment more than once. Example: copying an airline ticket and claiming the cost again on next month's expense reimbursement.

For each type of expense account fraud, offer a creative control mechanism that you would implement to eliminate that type of scheme. Explain your responses.