• Amazon on Tuesday said it backs federal legislation to legalize marijuana.
• The company said it is changing its drug testing policy and will no longer screen some workers for cannabis.
• Amazon is also adjusting its system that measures worker productivity, which has been a subject of scrutiny in the past.

Amazon is throwing its weight behind federal legislation to legalize marijuana and pledging to no longer screen some of its workers for the drug.

In a blog post Tuesday, Amazon's consumer boss, Dave Clark, said the company supports the Marijuana Opportunity Reinvestment and Expungement Act, reintroduced in the House late last month. The MORE Act would decriminalize cannabis at the federal level, expunge criminal records and invest in impacted communities.

"We hope that other employers will join us, and that policymakers will act swiftly to pass this law," Clark wrote.

Amazon said it would adjust its corporate drug testing policy for some of its workers. The company will no longer include marijuana in its drug screening program for any positions not regulated by the Department of Transportation, Clark said.

"In the past, like many employers, we've disqualified people from working at Amazon if they tested positive for marijuana use," Clark said. "However, given where state laws are moving across the U.S., we've changed course."

Clark said Amazon is also changing its system that measures worker productivity, known as "time off task."

Amazon tracks productivity rates among its warehouse workers, logging the number of packages they pick, pack and stow each hour. If workers take a break from scanning packages for too long, Amazon's internal systems will log it as a time off task and generate a warning, which can later lead to firings.

The measurement system was designed to identify issues with workers' tools and "only secondarily to identify under-performing employees," Clark said.

Starting today, Clark said, Amazon will measure time off tasks over a longer time period. "We believe this change will help ensure the Time off Task policy is used in the way it was intended," he added.

Amazon's time off task policy has previously come under scrutiny from employees and labor advocacy groups who argue it makes working conditions more strenuous and that it's used as a tool to surveil workers. These groups have also said Amazon's relentless pace of work contributes to rising injury rates among employees.

In his final letter to shareholders in April, outgoing CEO Jeff Bezos argued that Amazon's performance goals aren't unreasonable. However, he acknowledged that Amazon needs "a better vision for employees' success" and vowed to make the company "Earth's Best Employer and Earth's Safest Place to Work."

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