Critics argue the question will discourage noncitizens from responding, affecting the distribution of federal funding.

As the Supreme Court takes on the question Tuesday of whether the Trump administration can add a citizenship question to the 2020 census form, the city of Baltimore has a particular stake in whether it makes the right decision.

The justices should side with three lower courts, including one in Maryland, that have ruled against such an addition, which would certainly result in many immigrants not filling out the forms. Officials with the Census Bureau have said including the question could scare away 5.8 percent of households that include someone who isn't a citizen.

New census data show that Baltimore lost over 7,300 people, or 1.2% of its population, last year. The decline puts Baltimore's estimated population at 602,495. It's the biggest loss the city has suffered since 2001. Most people who left Baltimore went to other U.S. cities or counties. Baltimore has lost more than 18,500 residents since 2010, while its neighbors have seen population gains.

Baltimore needs as many people as possible counted as the city continues to watch a hemorrhaging of residents. The latest numbers released last week showed the biggest loss the city has experienced in a single year since 2001 and the fourth year in a row in which the city's population has fallen. About 1.2 percent of the population, or 7,346 people, moved out of the city, leaving 602,495 residents who still called Baltimore home.

Too often the city's systemic problems with crime, schools and other issues eventually wear on people with even the sincerest commitment to stick it out, leading many to move on when their kids reach school age or a burglary or assault hits a little too close to home. Others simply see more opportunities in the suburbs in the form of jobs for themselves and quality schools for their kids.

Reverse Baltimore's population slide: Bring on the immigrants

How does the city attract more residents than it loses? One answer, now and always, is welcoming immigrants, including some of those presently held at the U.S. border with Mexico.

But city officials have seen a bright spot in international immigration, people from other countries who are attracted to the city and not scared away. Nearly 2,000 new residents from abroad, including immigrants, students and overseas military personnel, moved to Baltimore in the last year measured in the census estimates. Without them, the city's population decline would be even worse — Baltimore lost more than 10,000 residents who left the city for other cities and counties.

City officials deserve credit for positioning Baltimore as one of the welcoming jurisdictions to which President Donald Trump has threatened to send migrants from the border. (Baltimore should be proud to be among those ranks.) Most recently, the city's Board of Estimates agreed to spend $1.25 million to help the immigrant rights and social services organization CASA de Maryland expand into an old theater in East Baltimore. Before she went on leave to recover from pneumonia (amid questions about her sales of "Healthy Holly" children's books), Mayor Catherine Pugh continued her predecessors' strong advocacy for immigrants and argued that the U.S. Census should not include a question about citizenship because people might avoid participating and make an accurate count impossible.

Census 2020: Making sure all Marylanders are counted

Although the U.S. Census Bureau and state agencies have official roles in the critical undertaking of the 2020 Census, we each have a role to play in engaging our own communities and working with nonprofits, community leaders and trusted voices to ensure that every single resident is counted.

And who could blame immigrants for not wanting to bring attention to themselves as the Trump administration has doubled down on efforts to round up those without citizenship and created an unfriendly immigrant environment? They understandably worry the information would be used punitively, rather than to get a accurate picture of who lives in the United States.

If the Supreme Court allows a citizenship question, Baltimore might see its official numbers drop even more, which would mean the loss of hundreds of million of dollars in federal funding to which the city should be entitled.

Federal judge in Maryland is third to block citizenship question on 2020 census

A third federal judge has blocked the Trump administration from adding a citizenship question to the 2020 census, ruling Friday that it poses a "substantial risk" of undercounting Hispanics and non-citizens.

The Constitution requires a Census every decade, and the results are used to calculate how much cities get in funding from a wide variety of federal programs, which amounts to about $900 billion a year nationally. It is also used to determine how Congressional districts are drawn and how many members states get in the U.S. House of Representatives, which could result in communities with large immigrant communities losing representation if those people aren't counted. (The constitution does not distinguish between citizens and non-citizens when it comes to apportionment.)

In his ruling, Judge George J. Hazel of the U.S. District Court for the District of Maryland in Greenbelt wrote that adding the citizenship question would unreasonably influence the accuracy of the census. Mr. Hazel didn't find enough evidence that the administration was trying to discriminate against non-citizens or that it violated anyone's civil rights, as some critics have argued.

Maybe the evidence wasn't there, but we find it hard to believe that there isn't an anti-immigrant motive behind the citizenship question, given the intolerance Mr. Trump and his staff have shown toward such populations.

That aside, there isn't really anything a question about citizenship will add to the analysis of our country's population, despite a tweet from Mr. Trump that said a Census without that question would be "meaningless." We should remind him that the 1950 Census was the last to ask about citizenship, and the results have worked out just fine since then. The Supreme Court should make sure that continues to be the standard.

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