https://www.avvo.com/legal-answers/authorized/do-i-have-to-prove-source-of-income-for-funds-in-r-5359171.html?answered=true

Do I have to prove source of income for funds in Racine County Wisconsin when there’s nothing that ties me to a crime nor the funds?  Was pulled over in Racine county for speeding violation; Not the driver; Narcotics dog was called and allegedly detected narcotics.  No narcotics seized or found traces nothing.  Was in possession of catalytic converters; Nothing stolen nor was from the state of Wisconsin.  Funds was placed under safe keeping at sheriffs department.  Now I’m being asked to provide proof of funds when there’s no crime committed funds aren’t pending confiscation.  I deal in mostly cash business as a sneaker reseller/custom car guy.  Is the burden on me to prove the funds?

Unless you have legal training, talking to the police is dangerous, and my guess is that you might have already might said too much.  The police might also know more that you think, meaning that your “speeding” arrest with a car full of hot auto parts might not have been an accident.  Answering your question, do you need to prove your source of income, the answer is technically “no,” but failure to do so might lead to your being charged with a serious crime, after which the government would need to prove your guilt beyond a reasonable doubt, but that might be much easier than you think.  On the other hand, even if you do try to prove your source of income, you could still be charged, and possibly even convicted  You therefore need experienced defense counsel to help you make this decision.