Amazon is being told to reveal how it decides which products get the “Amazon’s Choice” label in its online store.
Two US senators have written to Amazon asking it to say whether people or algorithms are making decisions about what gets the label.
They are worried that the Choice category can be manipulated via fake reviews and can mislead customers.
Amazon has been given until 16 September to respond to the letter.
The letter was written following an investigation by news site Buzzfeed which claimed many products in the “Choice” category are of poor quality or have their ratings boosted by fake reviews.
Research suggests products getting the Choice label sell better. OC&C Strategy Consultants found that products awarded the Choice label see a sales jump of about 300%.