At a time when Washington is promoting private investment in roads, bridges and other infrastructure, a 21-mile stretch of highway in Indiana provides what critics say is a cautionary tale.

The project, a partnership between the state and private investors, was signed by Vice President Mike Pence in 2014 when he was the state’s governor. It is two years behind schedule and only 60% built. The state is in the process of taking it over and will have to issue debt to finish it.

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