The Washington Post dropped the first part of a huge story about D.C.’s tax lien program this weekend, detailing how small property tax debts snowball into expensive foreclosures that cost D.C. residents their homes and benefit a small number of investors. Mayor Vince Gray has responded by calling for a moratorium on these sales.

“The Mayor found out about [the Office of the Chief Financial Officer’s] policy on tax-lien sales by reading about it in the Post article yesterday, and he was shocked and outraged by the revelations,” Gray’s spokesperson said in an email. “He is calling for an immediate moratorium on OCFO’s sales of liens and foreclosures, and will transmit emergency legislation addressing the situation to the Council for them to consider when they come back from recess. The legislation will put in place needed protections for homeowners – and particularly seniors, who appear to have been the group most frequently affected by this practice.”

As Gray pointed out on Twitter, the OCFO does not report to the Mayor’s office.

The Post’s 10-month investigation found that the tax lien program mainly affects minorites and those who lives in D.C.’s poorest wards.

Of the nearly 200 homeowners who lost their properties in recent years, one in three had liens of less than $1,000.

More than half of the foreclosures were in the city’s two poorest wards, 7 and 8, where dozens of owners were forced to leave their homes just months before purchasers sold them. One foreclosed on a brick house near the Maryland border with a $287 lien and sold it less than eight weeks later for $129,000.

More than 40 houses were taken by companies whose representatives were caught breaking laws in other states to win liens.

Instead of stepping in, the D.C. tax office created more problems by selling nearly 1,900 liens by mistake in the past six years — even after owners paid their taxes — forcing unsuspecting families into legal battles that have lasted for years. One 64-year-old woman spent two years fighting to save her home in Northwest after the tax office erroneously charged her $8.61 in interest.

The second-part of the series covers suspicious bidding and tomorrow’s conclusion will deal with mistakes made by the city. The authors of the series will chat with readers tomorrow at noon.

Update: As Zoe Tillman of The National Law Journal and Legal Times said on Twitter, the Alliance to Help Owners Maintain Equity sent Gray and Councilmember Jack Evans a letter last year about the program.

AT HOME – the Alliance to Help Owners Maintain Equity writes to highlight several flaws in the District of Columbia’s current real property tax sale system. We ask for your consideration of these flaws and request an opportunity to work with you in addressing them in a manner that not only ensures fair treatment for homeowners, but also alleviates the resulting heavy flow of litigation and adverse impacts on District government resources.

The current tax sale system deprives affected homeowners, many of whom are elderly or economically disadvantaged, of fair treatment, including constitutional protections.

Gray’s office said he never saw the letter because of a mail sorting mistake. Request for comment from Gray’s office and Evans’ office regarding if they received the letter has not been returned.