Executions have fallen by half since 1999. The number of new death sentences is about one-third what it was at the 1996 peak. Even in Texas, long the leading practitioner, death sentences are off by 80 percent. Several states that retain capital punishment have not administered a single lethal injection in the past five years. The exoneration of 138 death row inmates has weakened public support for the ultimate sanction. In a recent Gallup poll, 64 percent of Americans endorsed it, down from 80 percent in 1994, while opposition has nearly doubled.