It was a misunderstanding on her part, not a deliberate 'deception' on his (part). [=he didn't try to deceive her or lie to her]
The article describes the government's use of 'deception' [='deceit'] to gain public support for the program.
She 'practiced deception' on her unsuspecting clients. [=she deceived them]
(..) Don't you see? Her transgressions led the zealots to Dormammu. Kaecilius was her fault. And here we are, in the consequence of her deception. A world on fire. Mordo, the London Sanctum has fallen. The New York one has been attacked, twice. (..)2016 Doctor Strange