Conclusions
7. While we accept that the Department did not expect
the results to be so different from previous years', we are surprised
that they had not drawn our attention to the wide variations in
figures in earlier surveys, which should, on grounds of common
sense alone, have suggested that something was wrong. It was not
until our second hearing in April 2008 that we were given the
following figures by the National Audit Office:
Roadside survey conducted in June:
| Percentage Evasion in Active Stock
|
| All vehicles
| Motorcycles
|
| 2002
| 6.3
| 45.9
|
| 2003
| no survey
|
| 2004
| 3.7
| 20.0
|
| 2005
| 4.5
| 29.6
|
| 2006
| 6.1
| 38.0
|
| 2007
| 1.7
| 9.8
|
8. A fall in the motorcycle evasion rate from
45.9% to 20% between 2002 and 2004, followed by a rise to nearly
40% over the next two years, is so improbable that the Department
should have known there were serious errors in the surveys. Indeed
we understand that motorcycle bodies had repeatedly made this
point to them. Given this, the Department should have made clear
to us that their figures for road tax evasion could not be relied
upon.
9. We find it disingenuous to suggest that a change
in methodology that involved almost exclusive use of cameras and
enabled the results to be properly checked for the first time
was not a change in kind. Even if they were unable to give us
any early indications of the results of the June 2007 survey,
the Department should have made clear that the nature of the survey
had changed significantly.
10. We also find it incredible that from June
2007, when the data were collected, through publication of a NAO
report, a PAC hearing and publication of the PAC report, the Department
neither suspected that the figures were wrong nor gave any indication
to the Committee, but instead apparently waited until February
after adverse publicity to release new figures.
11. We are disappointed that the National Audit
Office did not scrutinise the Department's figures more rigorously.
The Committee does not have the resources to check the detail
of evidence put before it: we therefore expect the National Audit
Office to maintain its usual high standards in all cases.
12. Parliamentary scrutiny of the executive is
an important part of the constitution. It is dependent in large
part on the accuracy of evidence provided by witnesses. Government
departments are particularly responsible for ensuring that Members
are not misled, even inadvertently, by the evidence they provide.
As this case shows, offence can also be caused to law-abiding
sections of the community by the provision of inaccurate evidence:
this in turn can adversely affect the standing of Parliament in
the eyes of the public.
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