A group of US senators led by Cory Booker is intensifying pressure for Amazon to improve working conditions for its warehouse employees during the coronavirus pandemic.

On Wednesday, Booker and Sens. Robert Menendez, Sherrod Brown, Richard Blumenthal, and Kirsten Gillibrand sent a letter to Amazon CEO Jeff Bezos that questioned the company’s decision to fire an employee who demanded better health protections at the company’s facilities.

“We write to express our continued concern about working conditions at Amazon as well as recent actions Amazon has taken, including the recent firing of an Amazon warehouse employee,” reads the letter, which goes on to ask Bezos a series of questions about his company’s treatment of its US workforce. The senators are the latest to join a growing chorus of politicians, regulatory agencies, and employees who are questioning the company’s commitment to protecting its own workers during this international public health crisis.

While Amazon warehouse working conditions have long been scrutinized, the pandemic has amplified those concerns. During an unprecedented time when millions of Americans — or at least those who can afford to — stay home to try to slow the spread of the disease, Amazon warehouse and delivery workers are still laboring to send food, supplies, entertainment, and other items to Amazon’s customers.

And some of these employees say the company isn’t doing enough to protect them. In particular, they — as well as some of the company’s corporate employees — are criticizing company leadership for attempting to discredit a fired warehouse worker who was sounding the alarm bell about safety concerns. In the past few weeks, Covid-19 cases have been confirmed for workers in 50 out of some 500 Amazon warehouses in the US, according to reporting from the New York Times.

In response to the concerns raised in the letter, Amazon spokesperson Kristen Kish sent the following statement, in part:

“Our employees are heroes fighting for their communities and helping people get critical items they need in this crisis—we have nearly 500,000 people in the U.S. alone supporting customers and we are taking measures to support each one. ... Like all businesses grappling with the ongoing coronavirus pandemic, we are evaluating and making changes in real-time and encourage anyone to compare our overall pay, benefits, and speed in which we’re managing this crisis to other retailers and major employers across the country.”

In the last month, Amazon has upped its efforts to help employees by raising US warehouse worker pay by $2 an hour, doubling the hourly rate for overtime, staggering workers’ entries and exits, and providing two weeks of paid sick leave for employees with Covid-19 who have been placed under quarantine, among other efforts. But some Amazon workers on the front lines are still reporting overcrowding at facilities, a shortage of protective supplies such as gloves, and that workers are being denied paid time off when they fall ill.

Those concerns only increased when Amazon fired Chris Smalls, a warehouse worker in Staten Island, New York, who led one of several Amazon worker strikes around the country in recent weeks, demanded better health protections and pay. Amazon said that the company fired Smalls for returning to work after being asked to self-quarantine — a claim that Smalls denies. Soon after Smalls’s firing, a report from Vice News revealed the company’s top lawyer had referred to Smalls as “not smart, or articulate,” in a meeting attended by Jeff Bezos, and implied that executives should use his perceived weaknesses to help squelch worker unionization efforts.

As Recode previously reported, the leaked plans to discredit Smalls set off a wave of shock and anger within the company’s corporate ranks, some of whom openly critiqued their superiors on internal email lists visible to thousands of colleagues. This is a notable departure from the company’s usual culture of not airing internal disagreements in workplace forums.

Now, the senators behind this letter are asking Amazon’s CEO pointed questions — such as how many other employees besides Smalls were told to self-quarantine and what criteria Amazon is using to decide whether to shut down a warehouse after a worker tests positive for Covid-19.

Here’s the full list of the senators’ questions:

When did the fired employee come into contact with the diagnosed employee? When did Amazon ask them to self-quarantine?

How many other employees at the Staten Island location were told to self-quarantine and when were those employees told?

Will Amazon assure the public and its employees that they will allow their workers to freely and publicly address concerns they have in the workplace without fear of retribution?

What criteria is Amazon using to decide whether to shut down a warehouse after a worker tests positive? Will Amazon agree to temporarily shut down a warehouse whenever a worker tests positive?

How does Amazon plan on improving transparency during instances in which a worker tests positive? Will Amazon agree to let their employees know whenever a worker at their worksite tests positive?

How is Amazon ensuring that there are adequate essential supplies at their facilities, including disposable gloves and masks as well as essential supplies like hand sanitizer and disinfectant wipes?

Last month, Sen. Booker and a group of other US senators, including Bernie Sanders, sent Amazon a similar letter expressing their concerns and asking questions about warehouse working conditions.

Other politicians have also raised concerns. New York State Attorney General Letitia James called Amazon’s firing of Smalls “disgraceful” last week and urged the National Labor Relations Board to investigate the company. On the same day, New York City Mayor Bill de Blasio ordered the city’s Commission on Human Rights to investigate whether Amazon violated workers’ rights in firing Smalls.

It remains to be seen if Amazon will answer these senators’ questions, or if this will lead Amazon to make some of the changes its workers have been calling for.

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