By Brad Edwards

(CBS) — The office of Cook County Assessor Joseph Berrios determines the fair market value of the county’s more than 1.8 million parcels of property.

Owners who appeal those decisions, in hopes of lowering their tax bills, often hire lawyers.

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The 2 Investigators have found many of those lawyers regularly donate big bucks to Berrios’ various campaign funds – more than $1.9 million since 2012, according to a review of Illinois State Board of Elections data.

“It’s a clear conflict of interest,” says Dick Simpson, a professor and political watchdog. “The average person doesn’t sit around writing a check for Joe Berrios. The people who have a vested interest in getting Joe Berrios continually elected are the law firms that appear before the assessor’s office.”

Top political contributors include the law firms Sarnoff & Baccash, Amari & Locallo and Flanagan Bilton. The 2 Investigators found clients of those firms had their assessed property values lowered by nearly a half billion dollars in 2015 and 2016.

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In all, the three firms won more than 23,000 appeals.

Berrios declined a request for an on-camera interview.

In a statement, his spokesperson says, Berrios does not believe that accepting the donations is a conflict of interest and has no plans to discontinue the practice. It is not illegal.

“More than 1,450 attorneys and non-attorney representatives are registered to file appeals with the Assessor’s Office; and the Assessor has no involvement in the vast, vast majority of appeals. Among the small number of cases when decisions do come to him, Assessor Berrios has no regard for campaign contributions or lack of same,” the spokesperson says.

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Asked about the donations, Berrios’ campaign spokesperson says in a statement: “While we will not comment on any specific figure or contributor, generally campaign contributions are made by people who have an understanding and knowledge of the industry. Campaign finance laws are the same for everyone and election or re-election campaigns need funds to operate.”

Brad Edwards