Are there criminal charges for not paying debts?

No, you cannot be put in jail for defaulting on your debts. However, there are civil (i.e., monetary) avenues creditors may pursue to recover their money. This is not to say that any misdeed involving money is clear from criminal prosecution. Fraud and theft will still send you to prison.

One noteworthy exception to this rule is tax evasion. As illustrated in the case of Al Capone, you can certainly end up in prison for not paying your taxes.