Wondering why several sports streaming sites were shut down this week? So is Senator Ron Wyden, who asked whether such domain seizures infringe on free speech.

In a letter addressed to Attorney General Eric Holder and Homeland Security's Immigration and Customs Enforcement Director John Morton, Wyden called for greater transparency about how and why such domain seizures should be allowed to proceed.

"These seizures represent a major shift in the way the U.S. government combats copyright infringement in the digital environment," he wrote, as reported by Techdirt, going on to say, "I grow concerned when the methods used may not be effective and could stifle constitutionally protected speech, job-creating innovation and give license to foreign regimes to censor the internet."

Wyden raised a number of concerns, asking how the government measured the benefit of domain seizure, whether such sites were given due process, what exact policies regarding seizures were, and a host of questions on whether such sites were protected speech. He also asked for a full list of seized domains.

"The domain seizure process does not appear to give targeted websites an opportunity to defend themselves before sanctions are imposed," he wrote.

The third round of domain seizures, targeted at sports streaming sites, shut down 10 domain names belonging to 6 sites, including the Spanish site Rojadirecta.org, which is legal in Spain.

The sites taken down do not stream sports themselves, but provide links to places where users can watch, leading Wyden to ask, "Does the administration believe that hyperlinks to domain names that offer downloadable infringing content represent a distribution of infringing content, or do they represent speech?"

Wyden also called out an instance in the affidavit used to seize the site dajaz1.com, where the Agent downloaded four songs that were legally given to the site for the purpose of distribution.