The JetBlue president, Joanna Geraghty, warned employees against joining a union or participating in union activity in an email last month and claimed the company’s successes wouldn’t be possible if workers unionized, the Guardian can reveal.

“As a result of our success, there will always be union reps, and even fellow crew members, who try to convince you that paying dues and having a union would be a better way to go. However, a union would never be able to give you a list of accomplishments like this,” Geraghty wrote in the email seen by the Guardian.

The accomplishments cited in the email include a holiday party, adding more nail polish colors to the uniform policy, an app launch, and new bag scanners. “So if anyone asks you to sign a card, I’m asking you to decline. Don’t be fooled – the grass is not greener on the other side of the fence and you don’t have to look over that fence to see what unions have done (or failed to do) at other airlines,” the email said.

The warning from JetBlue’s management came in response to organizing drives by the Transport Workers Union (TWU) to unionize about 6,400 airport operation agents and roughly 1,000 mechanics at JetBlue.

“We watched the pilots get a union, we watched the inflight get a union, and we’re all Jetblue, we’re one big Jetblue family, but we’re now three different groups with three different rulebooks, and they pit us against each other,” said a JetBlue airport operation agent helping to lead the committee to organize a union. The agent requested anonymity out of fear of retaliation.

“The company is strongly against organizing. They say if we organize we are going to lose the culture. We are the culture, we make the culture, not the company and their very tight rules,” the worker added.

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The airport operations team tracks when inflight crew members arrive at each gate and is also responsible for flights getting out on time. Team members say they are often scapegoated for delays. “So you’re held personally accountable for things that happens day to day,” said another JetBlue airport operations agent involved in the organizing campaign. “They spend millions of dollars trying to keep unions out, but you should see our profit sharing this year, it was ridiculous.”

About 66% of JetBlue flight attendants, or inflight crew members, voted in favor of joining the Transport Workers Union in April 2018, despite a company-led campaign against unionization.

Ahead of the vote, JetBlue ran an anti-union website, KeepOurCulture.com, pushing for workers to favor a direct relationship with the company over a union. A company email seen by the Guardian that directed employees to the website noted: “I know there is a lot of fear around ‘at will’ employment. However the vast majority of employees in the United States fall into this category.”

The email added laws prevented workers from being terminated without cause, and that JetBlue did not “think a union grievance would work out better for our Crewmembers”.

Included in JetBlue corporate emails sent to workers advocating for them to vote against the union including a list of 10 reasons to vote no, such as “you can’t take the union for a test drive”, “your agenda gets replaced by theirs”, and “a union will change our company forever and not for the better”.

JetBlue also ran anti-union campaigns against efforts for pilots to unionize, which they ultimately succeeded in doing in April 2014. JetBlue and the public relations firm MWW received an award in 2012 from the Public Relations Society of America for its anti-union campaign focused on pilots.

Recently, JetBlue employees have reported the company handing out fliers to deter workers from signing union authorization cards.

“They put up a ferocious fight against us. Now I think they are going to pull out all the stops to try to prevent their 6,400 airport operations agents from unionizing,” said the TWU International president, John Samuelsen. “JetBlue puts themselves off as a benevolent, worker-friendly corporation and that’s not necessarily the case. Certainly if they were a worker-friendly corporation they would respect the democratic right of their workers to organize into a union.”

In an email, a JetBlue spokesperson said: “Choosing whether to have union representation is an important decision and should be a well-informed choice. We respect our crewmembers’ right to choose, but we do not believe a union will produce the best results for JetBlue crewmembers.”