Answer: Validity, misinterpretations, under-reported crimes
Explanation: Validity is a big problem when it comes to measuring crime, participants may not be truthful or may describe their actions as something that is not accurate. Misinterpretations refer to wrong or nonstandard definitions being used which may affect the accurasy of the reported crime. Under-reported crimes are also a problem because when dealing with them there is really no way of perfectly accumulating truthful facts behind them. This is because of the possibility that a large percentage of the crimes are not reported, therefore leaving us with possibly less than half of the actual amount.