The Department refers cases of suspected fraud to its Financial Investigations Unit (FIU) to assess the accuracy of the award. Its FIU detected 1,400 cases involving fraud in 2020–21 and increased the child maintenance owed by £10.9 million.74 The Department relies almost entirely on parents to detect child maintenance fraud. It told us that its “most fruitful references come from the receiving parent, often because it is the receiving parent who knows an awful lot about the paying parent’s situation and financial affairs as they chase things down” but that this was not its only route to detect fraud as it could pick this up through casework.75 However, the NAO found that in reality nearly all the Department’s referrals to its child maintenance FIU team come from receiving parents challenging the value of the assessment through the variation process. The NAO identified several reasons why a parent may not challenge the value of an assessment, such as not knowing enough about the other parent’s circumstances or not having access to the level of credible information required to substantiate a challenge, and that there may be other barriers, such as domestic abuse or financial control, that would prevent the parent from contacting the Department regarding suspected fraud.76 68 Qq 85–87; C&AG’s Report, para 25 69 Q 98; C&AG’s Report, para 2.28 and Figure 14 70 Q 86; C&AG’s Report, para 2.29 71 Q59; C&AG’s Report, paras 2.4 and 2.8 72 Q126 73 Q53; C&AG’s Report, para 2.6 74 C&AG’s Report, para 2.7 75 Q 53 76 C&AG’s Report, para 2.7 22 Child Maintenance