Overview
- A practical test by Prof. Claus Koss showed a freely available chatbot took longer than students and failed to judge a full tax case correctly, requiring repeated follow-up to produce usable answers.
- Research by Prof. Martin Jacob and other academic checks across many jurisdictions found AI often misapplies current tax rules and cannot reliably decide deductibility or legal outcomes.
- AI performs well at plain tasks such as explaining tax terms, listing common deductions, and producing checklists that help users gather documents before filing.
- Experts and the Bund der Steuerzahler strongly advise never to upload full tax returns, tax IDs, or bank details to general chatbots and to enter only short, non‑identifying text when seeking clarification.
- Tax authorities are increasingly using AI to detect false claims, so users remain legally responsible for filings and should consult trained tax professionals for complex, high‑risk, or uncertain cases.