178Reasonable excuse for failure to make return or pay tax
(1)If P satisfies Revenue Scotland or (on appeal) the tribunal that there is a reasonable excuse for a failure to make a return, liability to a penalty under sections 159 to 167 does not arise in relation to that failure.
(2)If P satisfies Revenue Scotland or (on appeal) the tribunal that there is a reasonable excuse for a failure to make a payment, liability to a penalty under sections 168 to 173 does not arise in relation to that failure.
(3)For the purposes of subsections (1) and (2)—
(a)an insufficiency of funds is not a reasonable excuse unless attributable to events outside P’s control,
(b)where P relies on any other person to do anything, that is not a reasonable excuse unless P took reasonable care to avoid the failure, and
(c)where P had a reasonable excuse for the failure but the excuse has ceased, P is to be treated as having continued to have the excuse if the failure is remedied without unreasonable delay after the excuse ceased.