Being selected for a tax audit does not automatically mean the government intends to charge you criminally, or even that they have uncovered any wrongdoing. However, even minor, or innocent mistakes can cause problems when uncovered during an audit. Usually audits are done either through the mail, or in-person at your home or business. Mail audits are usually requested by the tax agency for certain documentation or other supporting material you have that correspond with your return. These tend to be less onerous than when the agency wishes to meet with you at your home or office to review this information in person. It is important to involve experienced Certified Public Accountants if you are audited. If you receive a subpoena requesting the production of documents, you should contact a criminal lawyer who handles tax cases immediately.