E VER WONDER how two black guys from North Philly were prosecuted for their role in the 2013 building collapse on Market Street, but the well-heeled white guys who owned the property and supervised the demolition got away scot-free?

The lawyer for convicted contractor Griffin Campbell wants to know - particularly in light of new concerns about how embattled prosecutor Frank Fina selects his targets.

Defense attorney William Hobson plans to file a court motion today seeking Campbell's acquittal on the grounds that he and day laborer Sean Benschop were prosecuted because of their race and economic status, while white higher-ups escaped prosecution or were granted immunity to testify against Campbell.

"They're both black, and they're both economically at the bottom of the food chain," Hobson said of Campbell, 51, and Benschop, 44.

Campbell was convicted in October of manslaughter, aggravated assault and related charges for the June 2013 building collapse that killed six people and injured 13. Benschop, who was operating the excavator, pleaded guilty to similar charges.

But Hobson said yesterday that he now questions whether Fina - who he said supervised the 2013 grand-jury investigation - improperly pursued the pair while turning a blind eye to building owner Richard Basciano, architect Plato Marinakos and other white men involved.

"A senior prosecutor with more racial baggage coming out was running the show," said Hobson, referring to Fina.

Fina, a former state prosecutor now working for Philadelphia District Attorney Seth Williams, is under fire for his role in the so-called Porngate scandal involving sexist and racially offensive emails sent among law-enforcement officials.

In 2009, for instance, Fina sent an email with a fake motivational poster of a white man holding a bucket of KFC chicken and fending off two hostile black men, with a crowd of black men in the background. The caption: "Bravery at its finest." That email became public in August.

Last week, a Dauphin County judge ordered Fina to testify in the bribery case against a state representative from Philadelphia to determine if race had played a role in the investigation he led while working in the state Attorney General's Office. The office's email servers were a hub for porn and images that disparaged minorities.

State Rep. Louise Bishop's attorney has argued that the sting only targeted black lawmakers. Bishop is among six current or former Democratic officials - all black - who were arrested for allegedly taking money from a lobbyist-turned-informant.

Hobson said he will ask Philadelphia Common Pleas Judge Glenn Bronson to postpone Campbell's sentencing next month until Hobson can look into what he said appeared to be a "selective prosecution" based on "racial bias and hostility."

"I feel compelled by recent developments to bring this forward now," Hobson said.

Grand-jury investigations are secret, but Hobson said he personally dealt with Fina on behalf of Campbell in the criminal investigation following the building collapse. He said Fina was the supervising attorney.

Williams spokesman Cameron Kline yesterday declined to discuss Fina's role in the probe or to comment on Hobson's motion until it has been filed.

City Council on Thursday passed a resolution calling for Williams to fire Fina and two other prosecutors in his office tied to the Porngate scandal.

On Friday, Democratic state Rep. Mark Cohen called on Williams to "promptly drop" the bribery cases against Bishop and state Rep. Vanessa Lowery Brown, citing prosecutors' "hate-filled conversations and racial targeting memoranda" reported in the Daily News that day.

Yesterday, Democratic state Sen. Art Haywood called for an independent investigation of the state's criminal-justice system and new selection and retention standards to "weed out bias" among law-enforcement officials.

"Our commonwealth cannot be asked to tolerate the corruption and hate demonstrated by these emails," Haywood said in a statement. "The degradation of community members by public officials is absolutely unacceptable."

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