That was "Clues", where there's a preponderance of evidence that Data isn't being honest with Our Heroes, and it's later revealed that Picard specifically ordered Data not to be honest with them.
Sort of the HAL 9000 scenario.
Except that HAL actually killed the whole crew but one!! He wasn't so much stripped than stopped. They were even able to restart his system later, with a few less memories though... sort of what happens to someone after a long Coma.