The department once tried to stay out of state elections, urging caution. It is now pressing forward with claims of fraud as President Trump revives his unfounded assertions that elections cannot be trusted.

© Philip Cheung for The New York Times

At The New York Times’s Hard Fork Live event, Mr. Nadella addressed the backlash against artificial intelligence and President Trump’s comments about Americans sharing in the wealth of A.I. companies

© Mike Kai Chen for The New York Times

High temperatures across the San Francisco Bay Area will reach into the 90s on Thursday, forecasters said.

© Lea Suzuki/San Francisco Chronicle, via Associated Press