S. 1671, the Interstate Obscenity Definition Act, creates a federal legal definition of "obscenity" in the Communications Act of 1934 for the first time. The bill defines obscene visual material—including pictures, images, films, and videos—as content that appeals to prurient sexual interests, depicts or simulates sexual acts with the intent to arouse or gratify, and lacks serious literary, artistic, political, or scientific value. The definition applies to interstate and foreign communications regulated under federal law. The bill also makes a technical change to provisions governing harassing or obscene telephone calls. This legislation affects content creators, internet platforms, telecommunications companies, and federal regulators who enforce communications law, though it does not allocate new funding or establish specific implementation timelines.