ATLANTIC CITY — An allegation that Superior Court Judge Nelson Johnson is harboring bias in the trial of the city’s former police chief raised tempers in court Monday and left Johnson saying an attorney was “playing the race card.”

John Donnelly, attorney for former Atlantic City police Chief John Mooney, made a motion Monday for Johnson to recuse himself from the trial. The motion, which Johnson swiftly denied, would have resulted in a mistrial by necessity had it been granted.

The latest development in what has already been a contentious two weeks of testimony began with Donnelly tracing a path of potential connections between who Johnson ate lunch with last week and comments later made on a story on The Press of Atlantic City’s website. In a heated exchange, Donnelly suggested that Johnson could not be impartial.

“For you to start connecting dots ... that I am now in favor of the defense ... that is so petty and unprofessional that I'm embarrassed for you. That's how bad it is, John,” Johnson said referring to Donnelly.

Last week, historian Dennis Burroughs had lunch in Johnson’s chambers. Burroughs has also commented on The Press’ website agreeing with statements made by former Atlantic City Public Safety Director Robert Flipping favoring the city.

“I'm suspicious because I'm friendly with a black person? Is that what you're saying to me?” a visibly angered Johnson asked Donnelly, saying he was trying to figure out the source of the “pettiness.”

Burroughs, the historian who had lunch with Johnson, is black. Johnson is white.

In comments on The Press’ website, Flipping said he wasn't sure what would motivate former Atlantic City Prosecutor Ted Housel to bring up the issue of Mayor Lorenzo Langfordcq talking to known drug dealers at a homicide scene in testimony last week. He found the comments “deliberately off point and malicious,” he wrote.

Flipping, who was appointed public safety director in 2002, at one point was engaged in a legal battle with then-police Chief Arthur Snellbakercq that bears some resemblance to Mooney’s claims. Mooney is suing the city claiming he was targeted for a demotion because he was a whistle-blower. He also objected to the appointment of a public safety director, as Snellbaker had.

Burroughs responded that Flipping's comments were well said.

“People like ... Ted Housel have always been, in my thoughts, analogous to the image of the plantation overseer, and of course as Atlantic City was and is the 'plantation by the sea,’” Burroughs wrote.

“A Plantation by the Sea” is the name of a chapter in Johnson's book, “Boardwalk Empire,” which inspired the HBO television series of the same name.

Donnelly went on to suggest that because Johnson, the author of two books on Atlantic City's history, had used photos or had discussions with people who support Langford's administration, he could be unable to try the case fairly. Among those Donnelly mentioned were Joe Jacobs, a high-profile Atlantic City attorney with known ties to Langford.

When Donnelly suggested that Jacobs, who provided photos in one of Johnson's books, was a Langford supporter, Johnson replied, “Beats me who he supports.”

Johnson said Donnelly would be free to appeal the decision to the Appellate Division. David Azotea, another attorney representing Mooney, said he did not believe an appeal would be pursued.

In a separate motion also denied by the judge Monday, Donnelly asked to have prior testimony by former Atlantic City Business Administrator Michael Scott striken from the record. Last week, Scott testified that he was concerned about allegations that the city’s police dogs were acting improperly.

He said the issue would be of particular concern to the black community because police dogs had been used as a means of force to quell protests during the civil rights movement. As a result, the black community is sensitive to the use of dogs today, he said. That testimony wrongly injected race into the decision-making process, Donnelly said.

Defense attorneys argued that the history of the use of police dogs weighed on Scott’s decision to have them removed from the streets and therefore, was relevant.

“Mr. Scott could be extremely wrong about the history of African Americans and dogs, but it would speak to his motivation,” Langford’s attorney Robert Tarver said.

Scott’s testimony filled the remainder of the day Monday as he was questioned about a 2010 audit by New Jersey’s Office of the State Comptroller that pointed to millions of dollars going to extended leave buyouts in the Police Department. Scott said that report was the genesis of a plan to move personnel files out of the Police Department four months later in an effort to exercise better control over timekeeping.

Mooney has said he tried to block the move and acted as a whistle-blower. Housel has suggested in recent testimony it was a plan by the city administration to inject influence over the Police Department.

The defense had also planned to show the jury three large color photos of wounds allegedly inflicted by a K-9 on Monday, but following an evidence hearing Johnson disallowed the photos.

At issue was an argument by Mooney’s attorneys that they had only seen the photos in black and white during the discovery process despite requests for color copies.

Tarver said the photos were provided in color but that could not be immediately proven.

Former Atlantic City Public Safety Director Christine Petersen is expected to testify today.