With the push of a button, these covers hide the license plate, which makes it hard for police to track down cars involved in illegal activity such as sideshows.
"If these things are on the cars, and we can't detect and see these license plates, it prevents us from doing the follow up we do nowadays with these sideshows," Scott said.
Chiu sent cease and desist letters to four online retailers he claims sell these covers: Amazon, Walmart, Etsy and eBay. According to Chiu, it is illegal to sell these in California.
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"Our profound hope is that these four online retailers will do the right thing and ensure these products are not displayed on their sites," he said.
Sideshows are often recorded on cell phones and surveillance cameras. If the license plates are covered, it is harder for police to identify the driver. We reached out to the four companies. Walmart, Amazon and Etsy have not returned our request for a comment. eBay sent the following statement:
"Sellers are obligated to comply with applicable laws and eBay makes significant investments to help ensure a safe buying and selling experience for our customers. Consistent with our Encouraging Illegal Activity Policy, we are removing the relevant listings and will continue to monitor the marketplace. In addition to removing listings, we are updating our proactive controls to prevent sellers from listing these products."
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Chiu and Scott say these covers are not only involved in sideshows, but other kinds of crimes. The covers help criminals evade toll booth cameras and license plate readers on streets and freeways. They hope by cracking down on the sale of these covers they catch people involved in these crimes.
"These would belong in Gotham City," Chiu said. "But they do not belong here."