INCOME tax investigations in the Northeast can be even more complicated than those in other parts of the country. Given the large-scale exemptions granted to tribes under the law, the region’s politicians and business houses make sure they take full advantage of any loopholes. So when Income Tax (IT) sleuths raided the business and residential premises of three prominent business groups in connection with vast supplies of steel last September, it came as no surprise that documents seized from them revealed huge payoffs (for favours granted) to former steel minister and Congress chief whip in Parliament Santosh Mohan Deb and Mizoram Chief Minister Lalthanhawla.