Transportation officials handed out billions in federal infrastructure contracts without properly vetting recipients or monitoring their projects.

A report from the Government Accountability Office said $4.2 billion set aside for transportation project grants since the 2009 economic stimulus program has been awarded to hundreds of applicants for “reasons other than merit.”

Low-ranked projects beat out those with higher ratings for half of all grants issued through the program, which was meant to hand out grants competitively, the report said.

The government officials who selected lower-ranked projects could not provide documentation as to why they did so. There have been 271 grants under the program since 2009.

Previous reports have warned of the grant program's continuing contract issues, drawing the attention of Congress.

A May audit revealed that, while the Transportation Department used an evaluation system to rank potential projects before selecting which to fund, officials went back and inexplicably raised the ratings on 19 projects.

Sen. David Vitter, R-La., ranking member of the Senate Committee on Environment and Public Works, asked Secretary of Transportation Anthony Foxx in a May letter to provide Congress with documentation of the project-selection process amid concerns that contracts were satisfying only “political need and not the country’s infrastructure needs.”

The latest GAO review also said federal transportation officials have no way to ensure the money they distribute is producing effective results.

Because the department offers no framework for assessing the outcomes of infrastructure projects, it has no way of knowing if they “deliver sufficient results for the federal investment,” the report said.

DOT spokesman Ryan Daniels defended the department's management of the grant program, saying “the projects we funded last year will provide benefits to the nation for decades to come. The department has already developed reforms to address the documentation deficiencies identified by the GAO and those reforms are being fully implemented."