Those who wish to keep the internet free and open had best dust off their legal arguments. One of America's most influential conservative judges, Richard Posner, has proposed a ban on linking to online content without permission. The idea, he said in a blog post last week, is to prevent aggregators and bloggers from linking to newspaper websites without paying: Expanding copyright law to bar online access to copyrighted materials without the copyright holder's consent, or to bar linking to or paraphrasing copyrighted materials without the copyright holder's consent, might be necessary to keep free riding on content financed by online newspapers from so impairing the incentive to create costly news-gathering operations that news services like Reuters and the Associated Press would become the only professional, nongovernmental sources of news and opinion.