Annual Fraud Recovery Over Time: Should I adjust for inflation? I have a dataset of the total amount the U.S. Department of Justice obtained annually in settlements/judgments of government fraud cases from fiscal years 1988-2019.  There's a lot of variation, but more recently the total settlements/judgments range from around 1 billion to 6 billion dollars. 

We're trying to decide whether it makes sense to adjust the annual totals for inflation. Is there any reason not to? If we do, should we use CPI or GDP or something else?
You should definitely adjust for inflation, as you should with all monetary variables. I wouldn't worry using the CPI, you could use an alternative indicator as a robustness check to see whether the choice of indicator affects your main conclusions.