Experts have calculated the reforms proposed in the pre-Budget report will cost the Exchequer Pounds 2bn instead of the Pounds 10-40m estimated by the Treasury.
Advisers have told the select committee the changes will inadvertently encourage people to reclassify income as capital gains.
Liberal Democrat committee member David Laws will challenge Brown to defend his proposals.
Speaking before the hearing Law said: 'This is another major loophole which will allow well advised wealthier individuals to cut back their income tax liability.
'This is yet another example of the chancellor's meddlesome tinkeringapproach to tax policy badly backfiring.'
Links
Comments
Have your say on this article