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Sens. Bernie Sanders and Elizabeth Warren sent a letter to Amazon on Tuesday requesting that the company share details about "anti-union materials and activities" it reportedly distributed to managers at its Whole Foods subsidiary.

The letter points to a Gizmodo report from late last month that says Amazon produced and sent a 45-minute anti-union training video to team leaders at Whole Foods. The video reportedly states: "We do not believe unions are in the best interest of our customers, our shareholders, or most importantly, our associates. Our business model is built upon speed, innovation, and customer obsession--things that are generally not associated with union."

Sanders, an independent from Vermont, and Warren, a Democrat from Massachusetts, now want Amazon to share the video, a list of Whole Food locations where it was reportedly viewed and details on any external law firms or consulting companies that may have helped with its development.

The senators also want Amazon to provide copies of any additional materials related to organizing activities that may have been given to Whole Foods team leaders, as well as information on whether Amazon workers were fired or faced retaliation for speaking up against working conditions. Sanders and Warren request answers by Nov. 1.

When asked about the letter and the reported anti-union video, an Amazon representative provided the following statement:

"We have received the letter from Sen. Sanders and Sen. Warren, and will be responding to them directly. Amazon respects the individual rights of employees and has an open-door policy that encourages employees to bring their comments, questions, and concerns directly to their management team. We firmly believe this direct connection is the most effective way to understand and respond to the needs of our workforce."

In a subsequent email, Amazon said it complies with all federal, state, and local employment laws and that it respects the right of employees "to join a union or to choose otherwise."

Sanders and Warren are concerned that the alleged video's instructions to managers could lead to violations of the National Labor Relations Act (NLRA), such as spying on employees' union activities or creating the impression that such activities are being monitored. The video also reportedly tells Whole Food supervisors that they "might need to talk about how having a union could hurt innovation, which could hurt customer obsession, which could ultimately threaten the building's continued existence." Sanders and Warren said this could reasonably be interpreted as a "threat that an employee's workplace may close if he or she supports a union or engages in union activity," which they said is illegal under the NLRA.

The video was reportedly leaked just before Amazon said it would raise its minimum wage to $15 an hour in the US after mounting pressure from critics, including Sanders. The senators wrote that they appreciate Amazon's attention to raising wages, "But it is important to recognize that workers' rights do not stop at the minimum wage, and raising the pay of your lowest-paid workers, while important, does not give you a free pass to engage in potentially illegal anti-union behavior."

Sanders and Warren also note that without a union, Amazon can cancel the wage increase or cut compensation. The e-commerce giant was met with criticism when it eliminated monthly bonuses and stock rewards following its pledge to boost wages. In response, Amazon increased pay for some longtime warehouse workers.

Here's the full letter from Sanders and Warren:

2018.10.16 Letter to Amazon... by on Scribd

First published Oct. 17, 1:28 p.m. PT

Correction, 3:18 p.m.: Sanders is an independent.