Google and Amazon traded barbs Thursday morning in a House Judiciary Committee hearing about competition in the digital book market, joined by supporters and detractors of the proposed Google Books settlement.

The settlement, announced last October and awaiting judicial approval, would end Google's copyright liability for scanning and digitizing millions of books and set up a Book Rights Registry to distribute revenue to authors from Google's settlement payment and from Google Book Search. It would also allow Google to sell access to, and advertising for, digital books, including orphaned works -- books without an identifiable rights holder.

The settlement has elicited opposition from a wide variety of companies and advocacy groups that have expressed concerns about the antitrust and privacy implications of the deal. It has also drawn support among those who believe the arrangement will make books more accessible to a broader set of people.

In prepared remarks, David Drummond, Google's SVP of corporate development and chief legal officer, argued that Google's entry into the digital book market would free readers from the shackles of Amazon's Kindle.

"What we anticipate will revolutionize the way some people read books is an open cloud-based platform, where users buy and store digital books in online personal libraries accessible from any Internet-connected device," he said. "Amazon's Kindle approach links its online bookstore with its hardware device in a proprietary system, where users buy their books and device from a single source -- Amazon."

Google, he said, intends to partner with a variety of companies "to develop an open platform."

Elaborating on that point in a separate statement, Drummond addressed a point of confusion about the settlement, namely the misapprehension that Google alone will be able to sell the out-of-print books it has scanned.

"[W]e will let any book retailer sell access to those books," said Drummond. "Google will host the digital books online, and retailers such as Amazon, Barnes & Noble or your local bookstore will be able to sell access to users on any Internet-connected device they choose. Retailers can also pursue their own digitization efforts of out-of-print books in parallel."

With regard to in-print books, Google won't sell a digital version without consent from the publisher or author. That just leaves orphaned works as a problematic category of books -- Google will be able to distribute them without fear of prosecution but others, not being party to the settlement, will not have that assurance.