NEW United States tax breaks enacted last year are causing confusion for taxpayers and enforcement problems for the Internal Revenue Service, according to a government report issued yesterday, the deadline for filing individual returns.

By March 5, the IRS erroneously gave out US$24.2 million in Making Work Pay tax credits, according to the report by J. Russell George, the Treasury inspector general for tax administration. The IRS issued US$25 billion worth of the credits during the period, for an error rate under one-tenth of 1 percent.

The IRS also wrongly issued about US$4.7 million in tax credits meant for people who bought plug-in electric cars. The new tax breaks were part of the massive economic recovery package passed last year.

"Our report concludes that the IRS is having a mixed filing season this year," George said. "On the one hand, they are having difficulty implementing many of the changes created by the passage of the laws designed to stimulate the economy. On the other hand, the news is not all bad as the IRS is detecting and stopping more erroneous refunds this year."

The report covers returns processed as of March 5. At the time, the IRS had received about 61 million returns. The agency expects to receive about 140 million individual returns this year.

"Any time you have major tax changes you will see some confusion over it," said IRS spokesman Terry Lemons. "We are doing everything we can" to work through problems.