Which character says 'Identity theft is not a joke, Jim!'?

Dwight Schrute says, “Identity theft is not a joke, Jim!”

The line appears in the Season 3 episode “Product Recall,” when Jim Halpert arrives at work dressed as Dwight. Jim copies Dwight’s distinctive glasses, shirt, hairstyle, mannerisms, and serious speaking style. Dwight initially seems pleased by what he calls imitation, but he quickly becomes angry when Jim continues the impersonation.

Dwight’s dramatic warning is funny because Jim is not committing actual identity theft; he is simply performing an elaborate office prank. Dwight then retaliates by dressing as Jim, though his imitation is far less convincing. The scene is one of the show’s clearest examples of Jim’s long-running campaign to annoy Dwight.

The quote is sometimes misattributed to Michael Scott because Michael frequently repeats or exaggerates other employees’ jokes. Creed Bratton and Andy Bernard are also possible distractors, but neither delivers this line. Dwight’s unusually intense reaction and his belief that identity theft affects millions of families make the quote unmistakably his.