An email sent by Activision Blizzard (ATVI  ) chief administrative officer and former Trump official, Brian Bulatao, has landed the company in hot water, once again. Labor experts say the email was clearly a union-busting effort by the CAO.

Employees hope to use collective action to improve the working conditions at Activision. Currently, there is a campaign underway at the company to bring employees under the representation of the Communications Workers of America union (CWA). It was this campaign that Bulatao was responding to in his email to workers.

"We ask only that you take time to consider the consequences of your signature on the binding legal document presented to you by the CWA," Bulatao wrote in the email to 9,500 Activision Blizzard employees. "Achieving our workplace culture aspirations will best occur through active, transparent dialogue between leaders and employees that we can act upon quickly."

Just this month, workers at independent game developer studio Vodeo Games passed a 100% vote to join the first-ever video game developer union to be formed in North America. The union, Video Workers United, was formed with the help of CWA.

Activision Blizzard, known for its games "World of Warcraft", "Candy Crush", and "Call of Duty", has been embodied in controversy since July of this year when the state of California sued the developer over allegations of sexual harassment and gender discrimination.

According to the suit, Activision "fostered a sexist culture" on which "women were subjected to constant sexual harassment, including groping, comments, and advances". The suit alleges that Activision executives and human resources were aware of these issues and failed to act.

It has since been proven that Activision CEO Bobby Kotick had been aware of the sexual misconduct occurring within the company for years. Investors are calling for his resignation.

Along with the CA suit, Activision Blizzard is also facing an investigation by the Securities and Exchange Commission (SEC) regarding workplace sexual misconduct allegations.

"Instead of responding to their workers' concerns, they've opted to blast the most tired anti-union talking points straight from the union busting script," CWA's national organizing director, Tom Smith, told reporters.

Labor law experts say that Bulatao's email toes the line of what counts as legal persuasion rather than an illegal threat.

"The goal is to sound both menacing (consider the consequences) and friendly (keep our ability to have transparent dialogue), while avoiding making a clear threat," University of CA labor expert Catherine Fisk told NPR. "Threatening employees is illegal, but cautioning them is not."

However, some Activision organizers say that the company's behavior went beyond a cautionary warning.

"When I started organizing, there was a lot of internal pushback," Jessica Gonzalez, an Activision Blizzard employee and co-runner of a pro-unionizing Twitter account, told NPR. "I was getting vilified. It took a toll on my mental health."

Since then, Gonzalez has left the company, but she says she will continue to help workers organize for better treatment, specifically by gathering funds to support striking workers.

"I care enough about the people I work with. It's the people who make the freaking games so great. We should be nurturing that passion and not exploiting that passion," Gonzalez said. "Culture comes from the top down, but Bobby Kotick has had 30 years to fix the culture. It hasn't happened yet."