In the news, a courtroom artist was arrested today. I'm not surprised; he always seemed sketchy.
Why this joke works
Sketchy by Profession
Sketchy can describe someone who seems suspicious or untrustworthy. A courtroom artist is also professionally sketchy because the job requires quick drawings of legal proceedings. Read the first sentence like a short news bulletin and make the reaction sound unsurprised. The occupational meaning quietly supports the suspicion without needing any details about the arrest. Courtroom artists sketch proceedings when cameras are restricted, so drawing is a defining part of the person’s real job.
A closer look
The Professional Description Sounds Like Suspicion
A courtroom artist necessarily makes sketches, so “sketchy” can describe the person’s output. In everyday speech, however, the adjective suggests someone or something suspicious or unreliable. The arrest transforms that casual description into apparent evidence of character. The narrator’s “I’m not surprised” delivers confident hindsight, even though the only clue offered is perfectly normal for the artist’s job.
Fact behind the joke
Courtroom Artists Record Proceedings When Cameras Cannot
The Library of Congress preserves courtroom drawings as visual records of trials and hearings. Artists must observe quickly and capture people, settings, and moments while following court rules. Their work can help news audiences picture proceedings when photography or broadcasting is limited. Being “sketchy” is therefore an occupational necessity for the joke’s artist, not evidence that the person committed a crime.