C-Span did contact the speaker’s office to have it take down a clip from her blog — one shot by C-Span’s cameras at a House Science and Technology Committee hearing on global warming where Ms. Pelosi testified.

C-Span, a private nonprofit company financed by the cable and satellite affiliates that carry its programming, says that over more than 25 years of operating it has consistently asserted its copyright to any material it shoots with its own cameras.

You don't own the videos of government testimony. Carl Malamud has been working on changing that. He has started posting hearings into the public domain. Download them. Quote them in your podcast. Sample them in your music. Use this or it will go away.