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Part three of the Post‘s tax lien investigation finds 20 percent of liens sold accidentally. [Post]

Mayor Vince Gray and Jack Evans say they’re surprised by the investigation, but a group tried to tell them about the problems last year. [Post]

A tax lien sale moratorium will need legislation from the D.C. Council. [Housing Complex]

There’s more than one kind of problematic tax lien sale. [Housing Complex]

Without all the land secured, Gray is set to sign a labor deal for the D.C. United stadium. [NBC 4]

David Grosso plans to introduce pot legalization bill next week. [Times]

Metro ridership falls 4 percent. [WAMU]

With a double-digit drop on weekends. [GGW]

Vincent Orange gets fit. [LL]

Howard falls in the college rankings. [Post]

More details on Georgetown stabbings [Post]

15th Street NW bike lane repaving starts. [WAMU]

D.C. leads the country in unintended pregnancies. [WAMU]