WILMINGTON, Del. (AP) — Tesla founder Elon Musk took to a witness stand Monday to defend his company's 2016 acquisition of a troubled company called SolarCity against a lawsuit that claims he's to blame for a deal that was rife with conflicts of interest and never delivered the profits he'd promised.

And to the surprise of no one, the famously colorful billionaire did so in the most personally combative terms.

"I think you are a bad human being," Musk told Randall Baron, a lawyer for shareholders who was pressing Musk to acknowledge his mistakes in helping engineer the acquisition of SolarCity...