(1)  The amount of penalty tax is to be increased by 20% if, after the Commissioner has informed the taxpayer that an investigation is to be carried out and before the investigation is completed, the taxpayer took steps to prevent or hinder the Commissioner from becoming aware of the nature and extent of the tax default in whole or part.

(2)  For the purposes of this section, a taxpayer takes steps to prevent or hinder the Commissioner if the taxpayer –

(a) deliberately damages or destroys records required to be kept under the taxation law to which the investigation relates; or

(b) without reasonable excuse, refuses or fails to comply with a requirement made by the Commissioner under Part 9 for the purposes of determining the taxpayer's tax liability; or

(c) hinders or obstructs an authorised officer performing functions or exercising powers under that Part for that purpose.