Criminal tax law is a complex, evolving field of general law. The tax code changes almost daily and with it the disclosure obligations of the tax payer. The weakly defined line between legal tax avoidance and illegal tax evasion is constantly shifting. The legal developments in recent years have also been strongly characterised by numerous landmark decisions by the competent tax court, the first Criminal Senate of the Federal Court of Justice. These include decisions, which have now partially been implemented in law, on raised requirements for precautionary voluntary declarations to avoid punishment in accordance with section 371 of the Fiscal Code and on more stringent regulations for the determination of the legal consequences of tax offences. Successful defence in criminal tax offence matters depends on the constant updating and expanding of specialised knowledge in this field. For our daily work it is no less important to be able to draw on a wealth of criminal tax cases in many forms. This allows us to make the right decisions for each individual defence strategy.