Washington (CNN) House Oversight Committee member Rep. Alexandria Ocasio-Cortez slammed the Trump administration Wednesday for the controversial addition of a citizenship question to the 2020 census, saying the question was "magically added."

The Commerce Department announced last year that a citizenship question would be included in the upcoming 2020 census. The move has sparked controversy and a high-stakes court battle as critics say that asking about citizenship status will lead to an inaccurate population count which serves as the basis for decisions about how to allocate federal resources and draw congressional districts.

"What I want to know is why this question was added. Why two years have been shaved off of that five-year process. I want to know why we have skipped every normal mandated procedure in testing how this question gets added in the census," Ocasio-Cortez said during a committee meeting. "I want to know why it was -- why this question was magically added after we have seen that a political operative knew and detailed an intent to intimidate racial and immigrant communities for a partisan purpose, saying this will hurt Democrats and help Republicans."

Critics of the Trump administration's decision to add a citizenship question point to a newly disclosed 2015 study written by the late Dr. Thomas Hofeller, a Republican redistricting expert, who wrote that using "citizen voting age" population as the redistricting population base would be "advantageous to Republicans and Non-Hispanic Whites."

A Justice Department spokesperson said in May that the 2015 "study played no role in Department's December 2017 request to reinstate a citizenship question to the 2020 decennial census."

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