WASHINGTON (AP) — Sandra Day O'Connor, the first woman on the Supreme Court, announced Tuesday in a frank and personal letter that she has been diagnosed with "the beginning stages of dementia, probably Alzheimer's disease."

The 88-year-old's letter was addressed to "Friends and fellow Americans." And it was a farewell of sorts from a woman who was not only a trailblazer for women in the law but also for much of her quarter century on the high court a key vote on issues central to American life.

O'Connor said doctors diagnosed her some time ago and that as her condition has progressed she is "...