US tax agency chief resigns amid controversy over scrutiny for conservative groups

President Barack Obama has announced the head of the US tax agency has resigned after it emerged his staff singled out conservative groups for extra scrutiny.

He said that Treasury Secretary Jack Lew had asked for and accepted the resignation of Internal Revenue Service (IRS) Acting Commissioner Steve Miller.

In a letter to colleagues, Miller said he would leave his role in June, adding that there was a strong and immediate need to restore public trust in the nation's tax agency.

On Tuesday, the Treasury Inspector General for Tax Administration's report on the scandal placed the blame on 'ineffective management'.

According to the BBC, Obama told a news conference that he will do everything in his power to make sure nothing like this happens again.

In a short statement to reporters at the White House, Obama said he had reviewed the Treasury Inspector General for Tax Administration (TIGTA) report on the IRS's targeting of conservative groups and found the 'misconduct' uncovered was 'inexcusable'.

Miller took over leadership of the agency in November, when the five-year term of Commissioner Douglas Shulman ended.

At the time when conservative groups were targeted, Miller was a deputy commissioner who oversaw the division responsible.

According to the report, it has been revealed that IRS managers had allowed 'inappropriate criteria' to be developed and stay in place for more than 18 months, resulting in substantial delays in processing applications for tax-exempt status, and requests for unnecessary information, such as lists of donors.

Senior IRS officials told the watchdog that the decision to focus on conservative groups had not been influenced by any individual or organisation outside the agency.

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