How it rules on a Texas law requiring age verification on adult websites could shift the bounds of internet speech.

The Supreme Court seems open to a Texas law aimed at blocking kids from seeing online pornography. But the justices could still send it back to a lower court for more consideration of how the age verification measure affects adults’ free-speech rights.

The Supreme Court weighed whether an explosion in online pornography requires repudiating the court’s precedents concerning sexual content as the justices Wednesday heard arguments in a challenge to Texas’s age-verification law for porn websites.