May 31 (UPI) -- Advocates who oppose adding a citizenship question to the 2020 Census have filed new evidence with the U.S. Supreme Court, which they say proves the question about nationality is a strategy to get more Republicans elected.
The high court heard arguments on the issue last month and appeared split in their opinions. The Trump administration has said adding the question is intended to enforce voting rights, but the American Civil Liberties Union said in its filing Thursday evidence shows that's not true.
The ACLU said the filing shows the genesis of the citizenship question originated with GOP redistricting strategist Thomas Hofeller -- not Justice Department official John Gore, as Commerce Secretary Wilbur Ross has testified. The filing shows Hofeller wrote letters and conducted a study in 2015 that showed adding the question to the census would create an electoral advantage for "Republicans and Non-Hispanic Whites" because congressional maps would have fewer Latinos.
"Witnesses misrepresented the origin and purpose of their effort to add a citizenship question to the census," ACLU representative Dale Ho said. "Their goal was not to protect voting rights but to dilute the voting power of minority communities."
Ho added that members of the administration have "obscured" Hofeller's role through "affirmative misrepresentations."
Hofeller, who was also a GOP consultant, died last year. His daughter discovered letters on his computer hard drives that showed he was the strategist behind the citizenship question, the ACLU filing said.
Watchdog Common Cause filed a similar motion in a New York court Thursday.
"The new evidence, concealed by defendants here, strongly underscores the pretextual basis for defendants' decision to add a citizenship question to the 2020 Decennial Census," its motion said.
Judge Jesse Furman set a hearing for June 5 on the ACLU's motion to impose sanctions on government witnesses. A Justice Department official said they were unaware of new evidence and will file a response in court.
Solicitor General Noel Francisco testified this year the Justice Department had asked to add the question to next year's census to ensure it had accurate data to enforce the Voting Rights Act. Nearly two dozen states and several advocates have argued in court that the question would lead to an inaccurate population count.
Three federal judges have ruled that Ross' rationale for adding the question was unconstitutional and violated federal law. A New York judge said the question will "materially reduce response rates among immigrant and Hispanic households."
The Supreme Court is expected to rule on the matter in the coming weeks.