Google set up a searchable database of political ads last summer, following calls for greater transparency in the wake of Russia’s interference in the 2016 presidential election.

Nearly a year later, the search giant’s archive of political ads is fraught with errors and delays, according to campaigns’ digital staffers and political consultants. The database, the Google Transparency Report, doesn’t always record political ads bought with Google’s ad tools and in some instances hasn’t updated for weeks at a time, they say.

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