A coalition of Detroit homeowners and advocates insists that the city continues to systematically over-assess and over-tax some homes—a claim Mayor Mike Duggan’s administration vigorously denies.
Members of the Coalition for Property Tax Justice and Duggan administration officials, including Detroit’s chief assessor, discussed the issue at a sometimes-contentious Detroit City Council committee meeting on Thursday.
Both sides agree on two basic points. One is that during and in the aftermath of the Great Recession, Detroit did systematically over-assess the majority of its residential properties—from 55% to 85% of all homes from 2009-2015, according to one study. That was in violation of Michigan’s state constitution, which caps assessments at 50% of a home’s market value. It also led to inflated property taxes that sparked a wave of tax foreclosures from which the city has not yet recovered.
The second point is that since Duggan took over as mayor and overhauled the city assessor’s office, the problem has decreased dramatically. But where the two sides disagree is whether the city continues to over-assess some properties, particularly the lowest-value ones, leading to a disproportionate property tax burden on the poorest homeowners.
Data scientist Eric Langowski analyzed recent city assessment and property sales data on behalf of the coalition. He found that while assessments in violation of the state constitution have dropped dramatically—from 53% in 2016 to 12% in 2021—“the ones that are remaining to be over assessed are the lowest-valued homes.”
“The findings are that the lowest valued homes are still being assessed in violation of the Michigan State Constitution,” added Professor Bernadette Atuahene, a coalition leader and professor of law at the University of Wisconsin who has extensively studied Detroit’s assessment practices and resulting housing inequities.
But city assessor Alvin Horhn pushed back on the coalition’s assertions, calling its data analysis flawed.
“I reject the notion that we're overvaluing low-value properties, and that we're undervaluing high-value properties,” Horhn said.
Horhn acknowledged that with over 400,000 properties on Detroit’s tax rolls, it’s “statistically impossible” that all of them are assessed correctly. “But that's why we have an appeals period” where homeowners can challenge their assessments and tax bills, Horhn added.
If the coalition believes that Detroit continues to illegally assess properties, “Then take it to the people who can make this office comply with the state law,” Horhn said. “That hasn't happened yet. And I think that's telling."
Horhn’s comment drew a sharp rebuke from Atuahene, who accused the city of refusing to do an assessment ratio study to confirm what outside researchers have found. “We have about four different [studies] done by four different entities. We have even had those studies peer reviewed,” Atuahene said.
“There are still illegal assessments happening in Detroit. We have to suture the wound. We have to stop these over-assessments in Detroit so we can move on to conversations about compensation [for past over-taxation]. We cannot suture the wound if the administration is denying in the face of all of this data that a problem even exists.”
The two sides were able to agree on possible changes to the assessment process to make it more user-friendly, such as improving the city’s annual assessment notice and sending assessment data out earlier. Such changes would need to be approved by the City Council. The Council is also exploring possible avenues for compensating Detroiters who lost their homes to tax foreclosure due to over-assessment.
