MANY shoppers are just learning that stores such as Walmart and Costco have the right to check proof of purchase before a customer leaves.

However, there is a crucial rule that all retailers must follow and if this is violated, the search becomes illegal.

West Coast Trial Lawyers, a personal injury law firm has a YouTube channel with more than 7,000 subscribers.

The channel answers legal questions that viewers may have.

One question that was asked was if a store could make a customer show their receipt.

“Can stores legally require to show proof of purchase before leaving?” asked one of the hosts of the channel.

He explained that stores actually have the right to ask customers to show proof as part of loss prevention measures.

Checking receipts is part of standard practice at all Costco warehouses, according to its website.

This is done “to verify purchase receipts when customers exit our buildings,” the website read.

“We do this to double-check that the items purchased have been correctly processed by our cashiers. It’s our most effective method of maintaining accuracy in inventory control, and it’s also a good way to ensure that our members have been charged properly for their purchases.”

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This is also done to prevent theft, as organized retail crime has greatly affected stores in the last few years. 

Walmart CEO Doug McMillon said stores could close if theft didn’t drop.

“Theft is an issue,” he told CNBC. “It is higher than what it has historically been.”

However, there is still an important rule that retailers must follow when checking receipts.

“It must be non-discriminatory,” said the YouTuber.

“And they can’t use excessive force without reasonable cause.”

If a retailer violates this law, the search becomes illegal.

A customer can file a complaint with the store’s management if this is the case.

They are also advised to speak with an attorney as well.