I am afraid that without knowing all the facts and considerations as regards your personal tax liabilities and your tax return filing etc position it is impossible to say exactly where your penalties will lie.
Basically unless you have effectively been guilty of fraud then there is no way that your penalty would be 100%. However your tax investigation specialists are the ones that will have to deal with matters as much as they are able and the penalties will be considered in relation to years up to and then from 2008-09 as follows:-
The penalties for
•inaccuracies in returns or other documents (FA07/SCH24/PARA1), and
•failing to notify HMRC of an under-assessment to tax (FA07/SCH24/PARA2)
•the inaccuracy is contained in (or the under-assessment relates to) a return or other document which is due to be filed on or after 1 April 2009, and
•the return or other document (or under-assessment) relates to a tax period beginning on or after 1 April 2008.
For income tax and corporation tax cases the return is based on accounts with a basis period ending in the period covered by the return. For 2008-09 the accounts basis period may start before 1 April 2008. For example, a 2008-09 income tax return could include accounts with a basis period 1 November 2007 to 31 October 2008. The tax period is the period covered by the return (6 April 2008 to 5 April 2009) not the period covered by the accounts. If there is an inaccuracy in the 2008-09 return, the penalty will be under FA 2007 Schedule 24.
For Pre Fa2007 years (2007-08 and earlier) the penalty starts at 100% and you then get discounts depending on your
(I) Disclosure - up to 20% for full disclosure on challenge
(ii) Cooperation - up to 40% for full cooperation
(iii) Size & Gravity - up to 40% depending on how serious your tax evasion has been
For Post FA2007 you calculate the penalty in a slightly different way and I will give an outline in the following posting
regards and hope this helps
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