A third threat to free speech at the University of California, Berkeley has led to more censorship than political rioters or college administrators. It's the Americans with Disabilities Act. Berkeley is expensive. Out of state students must pay $60,000 a year. But for five years, Berkeley generously posted 20,000 of its professors' lectures online. Anyone could watch them for free. Then government regulators stepped in. The Americans with Disabilities Act stipulates, "No qualified individual with a disability shall ... be denied the benefits of ... services." As with most laws, people can spend years debating what terms like "denied," "benefits"...