There are a lot of similarities between field audit and tax
investigation. This is because both concern under-assessments of tax. Tax investigation
is like a in-depth field audit of which the tax involved is larger and the scope
of investigation bigger and deeper --- the investigation usually covers the past
six years of assessment instead of the one last year under field audit.
If the field audit
reveals serious tax avoidance or tax evasion, full investigation will take
place. The procedures adopted by field audit, such as: selection of case,
interviewing procedures, adjustments of assessable profits, tax penalties...
etc. are also used by tax investigators.