A Muskegon police officer, who is white and selling his home, is on administrative leave after a prospective buyer, who is black, saw Confederate flags and a framed, yellowing application to the Ku Klux Klan on display in the lawman's home.

Rob Mathis, the potential home buyer, posted a photo of the Klan application on social media, setting off an internal investigation of the officer — and an internet furor.

"The City of Muskegon requests your patience as we thoroughly investigate this issue," the city said in response to media inquiries, including calls from the Free Press. "Further information will be available upon completion of the investigation."

The new investigation may threaten to reopen a community controversy from 2009, when the officer, Charles Anderson, fatally shot a 23-year-old black man, according to an MLive news report.

Earlier this week, Mathis said in a Facebook posting and in news interviews that he and his wife had been house shopping for more than a month.

They looked at homes in Sterling Heights, Grand Rapids, Hudsonville and Muskegon.

Mathis said they thought the house in Holton, about 20 miles from Muskegon, "would be perfect." But as they walked through it they saw several Confederate flags and the Klan application, which Mathis posted a photo of on Facebook.

"I immediately stopped my walk-through and informed the Realtor that I am not writing an offer on this home and I am leaving now," he wrote, adding that he felt sick to his stomach. "To the officer, I know who you are and I will be looking at resources to expose your prejudice."

According to news reports, Mathis is a U.S. Army veteran who was born in Detroit. He said in a news interview with MLive he and his wife, Reyna, a Muskegon native, are looking to buy a home with more land.

He added in the interview that he suspects the homeowner put the application up to discourage nonwhite buyers from being interested in making a purchase.

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The Sept. 23, 2009 incident, however, could be a big problem for the police department and city as the latest social media controversy garners national media attention.

According to a news report, Julius Johnson was pulled over by police in a traffic stop, but ran away. Anderson, who had arrived on the scene as police backup, chased Johnson.

Anderson, according the report, was hit in the head during a scuffle with Johnson. He also fired once at Johnson, killing him. An investigation later cleared him of wrongdoing and concluded he was justified in using deadly force.

But, Johnson's family and the local NAACP chapterwere dissatisfied with the investigation's outcome.

Neither Anderson nor Mathis could immediately be reached by the Free Press.

The MLive report said Anderson has been with the Muskegon police force for more than two decades. It quoted him telling a reporter that he was told not to comment because the situation is under investigation.

Contact Ann Zaniewski: 313-222-6594 or azaniewski@freepress.com. Follow her on Twitter: @AnnZaniewski.

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