Early Uber investors Mitch Kapor and Freada Kapor Klein say the company needs to change its ‘toxic’ culture patterns

The first of Uber’s many investors have spoken out against what many claim to be the company’s sexist work environment and culture. Freada Kapor Klein and Mitch Kapor, both central figures in Silicon Valley in their own rights, posted an open letter to Uber CEO Travis Kalanick, expressing their concern that the company is attempting to manage its way out of the allegations former employee Susan Fowler made in an essay on Sunday.

The letter asks a question many have pondered in the aftermath of Fowler’s essay. Kalanick said he had tapped former Attorney General Eric Holder and Uber board member Arianna Huffington to look into the matter, but how could it be an independent investigation?

The duo wrote that they were “disappointed” to see that Uber chose a group of insiders to conduct the probe.

“Eric Holder has been working on behalf of Uber since at least last June, when he and his firm were hired to advocate on behalf of Uber to lawmakers concerning using fingerprints as part of background checks on drivers,” they wrote. “Arianna Huffington has held a board seat for about a year and is deeply invested in the company weathering the PR crisis. As the company’s Chief Human Resources officer, Liane Hornsey reports to Travis’ executive team.”

“To us, this decision is yet another example of Uber’s continued unwillingness to be open, transparent, and direct,” they continued.

In response to the letter, Holder and Tammy Albarran, a partner at Covington and Burling along with Holder, said they will conduct the investigation impartially.

“We will be thorough, impartial and objective,” they said in a statement. “We are conducting this review with the highest degree of integrity and professionalism.”

But Kapor and Kapor Klein — who said they were concerned circumstances will return to “business as usual” after the public relations nightmare blows over — are optimistic about the possibilities for change.

“If we believed it was too late for Uber to change, we would not be writing this, but as investors, it is now up to us to call out the inherent conflicts of interest in their current path,” they wrote.

So far, investors who have responded to Fowler’s claims at all are few and far between.

Kapor Klein, the founder of the Level Playing Institute, is also among the leaders of Project Include, an organization attempting to increase diversity and inclusion in Silicon Valley. In the letter, the Kapors say Uber had “countless opportunities to do the right thing,” including working with the organization on building out its diversity team.

As Recode reported, Kalanick has previously refused reporting diversity statistics and felt the company’s human resources team should focus primarily on scaling the company. Now it’s up to the company’s newly minted HR chief Liane Hornsey as well its new head of diversity and inclusion Bernard Coleman III to find ways to undo the culture that has made stories like Fowler’s possible.

They rightly point out that the company has been in this position before — what with its executives suggesting the company should be allowed to dig up dirt on journalists, its sexist ads and some of its own internal practices — and have often apologized their way out of it.

“Uber has been here many times before, responding to public exposure of bad behavior by holding an all-hands meeting, apologizing and vowing to change, only to quickly return to aggressive business as usual,” they wrote.

This article originally appeared on Recode.net.