The binding legal principles established are:
1. The term 'tax debt' in s 183 of the TAA does not require that an assessment to tax must exist at the time of the dissipation of assets. A tax debt exists by operation of law upon the occurrence of a taxable event, regardless of whether it has been assessed. An assessment merely determines the quantum of a pre-existing liability and renders it recoverable.
2. Section 183 of the TAA applies where a third party knowingly assists in dissipating a taxpayer's assets to obstruct the collection of a tax debt, even if that debt has not yet been quantified by assessment at the time of the dissipation, provided the underlying tax liability existed at that time.
3. Evidence given under oath at an inquiry conducted under s 50 of the TAA is admissible in subsequent civil proceedings pursuant to s 56(4) of the TAA. The word 'proceeding' in s 56(4) includes civil court proceedings and is not limited to proceedings under the TAA.
4. The confidentiality provisions in ss 56 and 69 of the TAA do not prohibit the use of inquiry evidence in civil proceedings, as s 69(2)(a) expressly permits disclosure by SARS officials as witnesses in such proceedings.
5. The determination of the purpose for which inquiry evidence may be used, its probative value, and the weight to be accorded to it, are matters for the trial court to decide, taking into account the circumstances in which the evidence was obtained and ensuring the fairness of the trial in accordance with s 34 of the Constitution.