<p>Provided is a detection device (102) which is connected to appliances inside a residence and to a power meter (100) that indicates the amount of power consumed by the appliances inside the residence, wherein the detection device (102) is provided with: a reception unit (1021) for receiving a power amount from the power meter (100); a collection unit (1024) for collecting usage states of the appliances; an appliance information retaining unit (1027) for retaining appliance information including the usage states of the appliances and the corresponding power consumptions of the appliances; and a determination unit (1025) for determining whether or not the power meter (100) has been manipulated, by comparing the power amount received by the reception unit (1021) and a power consumption amount estimated from the usage states of the appliances by using the appliance information. The determination unit (1025) determines that the power meter (100) has been manipulated if there is a difference that is equal to or greater than a predetermined threshold value between the estimated power consumption amount and the power amount received by the reception unit (1021).</p>
