Key legal question
Whether the taxpayers could invoke legitimate trust based on an alleged prior telephone assurance by tax officials.
Extracted holding
The prerequisites for protection of legitimate trust were not clearly proven, especially because there was no written confirmation and the alleged assurance could not be reliably attributed to the competent authority.
Extracted reasoning
In tax matters, trust protection is applied restrictively. A mere unsubstantiated claim of a telephone assurance is insufficient; prior practice can be changed if it was legally incorrect.