Tim Cook, chief executive officer of Apple Inc., speaks during the Apple World Wide Developers Conference in San Francisco in June. He lamented Thursday that the "senseless killings this week remind us that justice is still out of reach for many."  Photographer: David Paul Morris/Bloomberg

Having spoken out in increasingly vocal fashion on issues such as gender equality, gun control and gay rights, a few tech leaders and companies are making their voices heard on social media in the aftermath of the fatal shootings of two black men and five police officers, expressing grief for the victims and their families or calling out divisiveness amid escalating racial tensions.

In a series of tweets, Apple CEO Tim Cook lamented Thursday night that the "senseless killings this week remind us that justice is still out of reach for many," sharing a tweet from civil rights activist Rep. John Lewis (D-Ga.) and saying "We can and must do better." On Friday, he again took to Twitter to express sympathy for the officers' families and the Dallas community, adding that "justice cannot be gained through violence" and sharing a Martin Luther King, Jr. quote: "We must all learn to live together as brothers, or we will all perish together as fools."

On its official Twitter account, Google wrote Thursday that "#AltonSterling and #PhilandoCastile's lives mattered. Black lives matter. We need racial justice now," adding a statement that the company is "devastated by the senseless deaths" of the two men and held vigils in their memory.

Other CEOs known for being active on social issues -- or who lead social media companies -- also commented on the events. Salesforce.com CEO Marc Benioff, known as a leader of corporate America's fight against bills that would diminish gay rights, shared tweets about gun violence and (twice) quoted Martin Luther King: "We learned to fly like birds, & swim like fish, and yet we haven't learned to walk the earth as brothers & sisters." Mark Zuckerberg issued a statement of his own, part of which referred to a video shot by Castile's girlfriend, Diamond Reynolds: "while I hope we never have to see another video like Diamond's, it reminds us why coming together to build a more open and connected world is so important -- and how far we still have to go."

As companies and business leaders become more engaged in social issues, it's possible such comments could prompt more business leaders outside technology to speak out on a topic -- racial tension -- that has gotten much less public attention from corporations than other issues, such as gay rights. More than 200 companies, for instance, have signed a position letter from the Human Rights Campaign opposing North Carolina's HB2. Some, such as PayPal and Deutsche Bank, took further action, abandoning investments or freezing planned expansions in local areas.

As author and advocate Janet Langhart Cohen wrote in an op-ed in the Washington Post in April, "the corporate titans who issued their démarche may truly have been offended by the denial of basic human rights to a historically oppressed segment of our society," referring to efforts by business leaders to defeat bills in states such as Arizona and Georgia that threatened to erode gay rights. "Regrettably, this corporate zeal has yet to be extended to people of color."

Communication experts say that may be because the issue of racial justice has become more divisive and politically charged. "There are people who are going to complain you’re siding with one group -- supporting the police or supporting Black Lives Matter," said Paul Argenti, a professor at Dartmouth's Tuck School of Business who studies corporate communication strategy, in an interview. "It's a lot more dangerous for companies to take a [stand] on this." 

One CEO who has tried to bring attention to racial tension, of course, is Starbucks' Howard Schultz, whose #RaceTogether campaign -- part of which involved getting baristas to write a hashtag on coffee cups and talk with customers about race -- was met with spectacular backlash. Watching that reaction may have given other CEOs pause.

"I think [Schultz] had his heart in the right place for sure, but I think it kind of trivialized the issue," Argenti said. "It angered people who were white. It angered people who were black. It’s a really good example of what can happen." (A Starbucks spokeswoman said in an email that she was not aware of any statement the company was planning to make following this week's events, but pointed to remarks Schultz made at the company's annual shareholder meeting in March, when he said "our reservoir is running dry -- depleted by cynicism, despair, division, exclusion, fear and yes -- indifference.")

Tom Andrews, president of consulting for SYPartners who has worked with leaders on public responses to social issues, says another reason companies may not be as active on race could be a lack of guidance on how to talk about it. "We have a language for the LGBT community -- there's been such a movement around creating that language you can trace right back to the [gay rights advocacy group] Human Rights Campaign," he said in an interview. "A lot of CEOs feel so awkward about race diversity and how to address it. They can't go there. They don't have a language for it."

Still, some are sure to try. Leslie Gaines-Ross, chief reputation strategist for Weber Shandwick, said in an e-mail that she expects to see more CEOs speak out on this week's events in coming days, though she warns "they need to carefully consider their influence on all their stakeholders, particularly employees and customers who are personally impacted by these events in different ways."

Meanwhile, Andrews thinks when CEOs do find the words, putting them in a tweet may seem short of taking real action. Andrews thinks moves like the one by JetBlue to offer free airfare to family members following the mass shooting in Orlando and to police officers wishing to attend the funeral last year of slain New York police officer Brian Moore, come off with real authenticity.

He thinks it could take longer -- perhaps even into the next generation of CEOs -- before race becomes a "productive dialogue" among corporate leaders. In the very near term, those who do speak out face the difficult challenge of seeming genuine in the face of horrific tragedy.

"What do any of us say when something horrible happens?" Andrews said. "You can only grieve."

Read also:

Howard Schultz wants you to try some civility with your coffee

This advertising agency turned its entire home page into a powerful #BlackLivesMatter message

CEOs are getting more political, but consumers aren’t buying it

Corporate America's embrace of gay rights has reached a stunning tipping point

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