Senate Commerce Chairman Jay Rockefeller, D-W.Va., announced Friday that he has been investigating "mystery charges" on telephone bills for several months.
Although the investigation is ongoing, Rockefeller said the practice of third-parties placing charges on phone bills has raised "serious concerns."
According to a statement from the committee, investigators are looking at AT&T, Verizon and Qwest to determine the companies' role in "cramming," which the committee defines as a "deceptive practice that involves placing unauthorized mystery charges on telephone bills."
The committee has been looking at the problem since as long ago as June, when Rockefeller sent the three major phone carriers letters requesting information about third-party companies that are allowed to place such charges.
So far, investigators have determined that many of the companies allowed to charge consumers have faced customer complaints, received failing grades from the Better Business Bureau, and often charge for services that are offered for free or through existing service plans, according to a committee statement.
"Last year, we put an end to an online practice that cost Americans more than a billion dollars in unauthorized charges on their credit and debit cards," Rockefeller said. "I'm continuing this fight -- if unauthorized charges are being placed on consumers' telephone bills, I'm going to put a stop to it."
The committee is now looking deeper into the relationships between major telephone service providers and the companies suspected of "cramming."