A few years back, Oakland’s city auditor found that two council members — Desley Brooks and Larry Reid — violated a law by interfering with city staffers who were awarding a city contract involving the redevelopment of the former Oakland Army Base.

After examining thousands of emails and interviewing more than three dozen people, then-auditor Courtney Ruby concluded in 2013 that Brooks and Reid appeared to favor one company for a roughly $2 million contract: Turner Group Construction.

No charges were filed, and Turner, which has offices in Oakland, Richmond and San Francisco, wasn’t accused of wrongdoing. Another company was awarded the contract.

Now, Turner Group Construction is back in the news — this time getting hammered by questions of fraud.

Last week, a federal grand jury indicted eight people following a bid-rigging investigation. Two of the people charged were Turner Group Construction executives: Chief Operating Officer Lance Turner, 57, of Oakland and Chief Financial Officer Len Turner, 56, of San Leandro. Both face charges of conspiring to defraud the U.S. Department of Energy.

Another of the people charged happened to be Reid’s son, Taj Reid, 46. In addition to a charge of conspiring to defraud the U.S. Energy Department, he faces charges of conspiring to receive a bribe and receiving a bribe.

According to the indictment, the Turners engaged in bid rigging for a contract to renovate a Department of Energy-owned building at Lawrence Berkeley National Laboratory. The Turners were allegedly aided in the scheme by Taj Reid.

Taj Reid and the Turners allegedly colluded with a “developer” willing to pay bribes. The “developer” was actually an undercover FBI informant.

The Turners allegedly agreed to submit a higher bid so that the developer could secure the contract with a lower bid. In return, they’d receive cash or the promise of construction work once the contract was awarded, according to the U.S. attorney’s office.

Taj Reid also is charged with conspiring to make an inside deal on contracts for two residential construction projects involving veterans. He allegedly plotted with Eric Worthen, 45, of Pleasant Hill, a former California Department of Veterans Affairs employee. Worthen and Taj Reid allegedly accepted $12,000 for the two deals.

They and the other defendants in the case are due to make their first court appearances Monday in San Francisco. The indictments are a result of an FBI sting operation in 2012-14 that led to the convictions of state Sen. Leland Yee, San Francisco political consultant Keith Jackson and Raymond “Shrimp Boy” Chow, leader of a Chinatown community organization.

It was Jackson who introduced the informant to Taj Reid, according to the U.S. attorney’s office.

None of this looks good for the Turners. And it certainly casts an even darker cloud over what happened back in 2013 at Oakland City Hall, where Larry Reid and Brooks were found to have improperly intervened on behalf of Turner Group.

What deeply troubles me is that Turner Group is a pillar of the East Bay’s black community, an example of success. I know that black-owned construction businesses must stay above ethical sinkholes, by strictly adhering to all codes and regulations, to gain recognition — and repeat business. Corners can’t be cut; they must be smoothed to specifications, perfect.

Founded in 2005, Turner Group has worked on several high-profile Bay Area projects, including the renovation of the Fox Theater in Oakland and the Boys & Girls Club’s Mission Clubhouse in San Francisco. And Turner has a reputation for creating desperately-needed work opportunities for the formerly incarcerated.

But what will Turner’s reputation be after two of its highest-ranking officers have their day in court?

San Francisco Chronicle columnist Otis R. Taylor Jr. appears Monday, Wednesday and Friday. Email: otaylor@sfchronicle.com Twitter: @otisrtaylorjr