Thought police? US supreme court upholds child pornography ban

From guardian.co.uk. What I find most interesting about this decision is the extent to which it depends on what people think they are doing. [All emphases added.]

[In a 7-2 decision the] court found that the language of the statute requires that the offender believe him or herself to be offering child pornography, and the offender must intend that the listener believe the material to be child pornography. …

The statute does not require that an offender actually possess child pornography, but criminalises promotion and advertisement of child pornography, for example an internet post describing child pornography available for trade or sale. …

Justice David Souter wrote the dissenting opinion, joined by Justice Ruth Bader Ginsburg. They were troubled that the act could conceivably be used to punish someone for promoting images that didn't in fact portray children, so long as the person believed them to.