A Stock Phrase used by characters looking to enhance their credibility in dealing with situations or problems that have arisen, where X is usually a type of occupation ("Doctor" being the most popular, by far). Certain jobs and occupations, like practicing medicine, are so universally respected that anybody merely claiming to be of that profession is enough for that person to be taken seriously.
When a problem arises where one's specific job skills and talents can be put into practice, such as after a D.I.Y. Disaster, somebody claiming to be a licensed plumber or architect can easily become a savior, and a cocky hero protagonist full of confidence in one's own expertise gets a pithy one-liner that can be delivered whenever held in doubt.
However, more often in many comedic situations, a speaker may call attention to their personal occupation or area expertise at a time when it would be completely irrelevant to a problem or issue at hand, or, taken to its furthest extreme, the speaker may be revealed as a fraud lacking all of the expertise being claimed.
Subtrope of Appeal to Authority; Sister Trope to I'm Not a Doctor, but I Play One on TV and Not That Kind of Doctor; Inverse trope of I'm a Doctor, Not a Placeholder, when a speaker recognizes that their personal expertise is not applicable to the situation at hand. Likely to be the first of many Doctor's Orders in a medical emergency.
- Trafalgar Law from One Piece tends to announce his profession with such a line. Though, it doesn't help that, in addition to being a doctor, he's a pirate. And, OH YEAH, his moniker is "Surgeon of Death," which is well justified with the fact that his Devil Fruit power enables him to turn any space into an operating room and manipulate anything within according to his will. Nonetheless, his medical skills are legit, considering how he used them to save Luffy and Jimbei from certain death.
- Played for Laughs in Osamu Tezuka's The Crater. The protagonist finds a nude woman on the beach and rushes to Tezuka-sensei. Tezuka insists that he puts on a set of clothes by himself because he's a doctor.
- Actor Allusion: Tezuka is a trained medical doctor.
- In Naruto, during the Chuunin Exam's arc, Kabuto (disguised as an ANBU) says "Don't worry. I'm a doctor" to Kiba, while he heals Hinata. Surprisingly, he doesn't seem to have any strange intentions with her at the moment.
- A Dr. Pepper ad campaign where "doctors" like Dr. Dre, NBA Hall of Famer Julius Erving ("Dr. J"), and Gene Simmons ("Dr. Love") use, "Trust me, I'm a doctor," as a slogan. They also give this trope and their own commercials a send-up with retired NFL linebacker Michael Strahan saying, "Trust me. I've sent people to the doctor!"
- A TV advertisement for the Capital One Venture Card with Alec Baldwin ends with Alec beginning to fiddle with the controls in a plane's cockpit while assuring the pilot, "It's okay, I've played a pilot before."
- The above image comes from the 2000 AD strip "Thirteen." His name is Durant, calling himself a doctor like that doesn't really have much to do with preceding or later events in the story, and he's not really a doctor after all.
- Matter-Eater Lad of the Legion of Super-Heroes once said, "Trust me, I'm a politician" (Him being a comedic character and politicians being Acceptable Targets).
- In Omega the Unknown, the doctor who treats James-Michael says, "Trust me, I'm a doctor," only to turn him into an experiment.
- Loki, in the Danish comic Valhalla: "Trust me! I am the god of lies!"
- In one of Alan Moore's Abelard Snazz strips, a man who has doubts about trusting the title character with what little remains of his money for planned ruse at a gambling casino is assured, "Trust me, I'm a genius!" By the end of the story, Abelard loses all of the man's money.
- From Sherlock Holmes (2009):
Holmes: Madam, I need you to remain calm. And trust me, I'm a professional. Beneath this pillow lies the key to my release.
- Also, when Watson is choking Dredger, he reassuringly tells Dredger, "Relax, I'm a doctor."
- The line, "Trust me, I'm a doctor," is said by Dr. John McCabe in The Beyond.
- In Muppets from Space, when Ed, examining Gonzo, notices that Gonzo has no nostrils, he asks, "How do you smell?" To which Rizzo the Rat responds, "Awful. Trust me, I'm his roommate."
- A non-sequitur example can be found in Slacker, where a woman keeps intoning, "You should quit traumatizing women with sexual intercourse. I should know. I'm a medical doctor. I own a mansion and a yacht."
- From Animal House:
Otter: (Rising in a disciplinary hearing) Point of parliamentary procedure!Hoover: Don't screw around, they're serious this time!Otter: (aside) Take it easy, I'm pre-law.Boon: I thought you were pre-med.Otter: What's the difference?
- Another variant from Ghostbusters (1984): "Back off, man, I'm a scientist."
- Monty Python and the Holy Grail: Doctor Piglet and Doctor Winston try to assure Galahad that they are doctors during his stay at Castle Anthrax.
- Dumb and Dumber - Lloyd runs down an airliner boarding ramp to get a briefcase to its owner, shouting at the attendant "It's all right, I'm a limo driver!" Too bad there's no plane at the end of the ramp.
- At the end of the movie trailer for Shock Treatment, Dr. Cosmo McKinley assures viewers, "Trust me, I'm a doctor", after saying that they'll be "pathetically crazy" about the movie.
- In Love at First Bite, "I'm a doctor — I know what I'm doing" is practically a Catchphrase for the heroine's would-be boyfriend and vampire hunter.
- In Transporter 2, the mook that replaces the doctor says this to Frank. He couldn't sound less convincing if he tried.
- In Stephen King's Misery, when Annie is about to cut off Paul's leg to punish him, she says: "Don't worry. I'm a trained nurse." She is, but that doesn't make it much better.
- Fear and Loathing in Las Vegas has a lot of fun with this, with Raoul Duke's repeated assurances that he is a doctor of journalism, and Doctor Gonzo's favorite phrase, "As your attorney I advise you to..."
- In the Greyhawk Classics novel Queen of the Demonweb Pits, Escalla's Catchphrase—"Trust me! I'm a faerie!"—always precedes a disastrous event.
- Parodied in Maskerade, when Nanny Ogg makes her way through a crowd to the scene of an accident by saying "Let me through, I'm a nosy person."
- In Going Postal and Making Money, Moist manages to pull off "I'm a criminal. Trust me." This is because Discworld has a high incidence of belief in At Least I Admit It and the reliable traitor; you can trust Moist precisely because he can admit he's here to trick you out of your money.
- A brand new series on TBS - Trust Me, I'm A Game Show Host.
- Saturday Night Live parodies of The View with Tracy Morgan as Starr Jones would always see Ms. Jones begin every single sentence in a discussion noting, "I am a lawyer" followed by an observation about the news story or subject being discussed that is completely obvious.
- The British reality TV show Trust Me I'm a Beauty Therapist featured eight British celebrities training to become beauticians.
- The sketch comedy show In Living Color! had a character named Fire Marshall Bill, played by Jim Carrey. Insane, masochistic, and Nightmare Faced, it's no surprise that when he says some variation of "Don't worry, I'm a fire marshall", it's of no reassurance and it doesn't help that he has a tendency to say that right before blowing up the building that he's in.
- The Doctor Who episode "The Eleventh Hour" had the line, "Trust me; I'm The Doctor."
- Similarly, in one episode, cruise line mogul Max Capricorn's company slogan is "You can trust me, my name is Max." (Twinkle Smile) You can't trust him.
- David Tennant owns a shirt that says, well...◊
- Matt Smith has said it at least once already, but the truly marvelous example is from 'The Rebel Flesh,' where when his over-foreshadowed 'ganger-clone finally appears it has several lines before the camera finally focuses on it—him, and then finishes up, "Trust me. I'm the Doctor." It's supposed to be creepy, but the episode is suffering from severe Aesop Amnesia, so many viewers are actually kind of relieved he's there.
- The CSI episode "The Theory of Everything" has Hodges insist, "Trust me, I'm an expert."
- An early episode of Jekyll sees Hyde note, "Trust me, I'm a psychopath."
- How I Met Your Mother: "Ted Mosby, architect. Trust me."
- Trust Me, I'm A Doctor was the name of a show (and, later, an accompanying book) on BBC Two that focused on the state and quality of health care in Britain. Combining factual reporting and satire, the purpose of the program was to teach viewers that doctors are not infallible and that people should learn as much about their own health care as possible.
- House certainly isn't afraid to mention his profession in order to establish his authority or otherwise be a snarker. Once, after bluntly telling a female patient that he wants to inspect her vagina, he tells her, "I'm a doctor, so it's okay."
- The True Blood episode where Sam reveals to Sookie that he's a shapeshifter gives us the line, "I'm not the killer, I swear. I'm a shapeshifter."
- On Star Trek: Deep Space Nine in the episode "Move Along Home," Quark assures Odo in a speech, "Trust me, I'm a gambler," explaining why he should take the shortcut in the chula game. Hilariously, it backfires.
- Bananas in Pyjamas had a character name "The Rat in the Hat" who's catchphrase was: "Trust me, I'm a Rat".
- A Bit of Fry and Laurie discusses the concept of this in a sketch wherein a doctor prescribes tobacco cigarettes for chest problems.
Patient: But these give you lung cancer, bronchitis and emphysema, don't they?
Doctor: What on earth gave you that idea?
Patient: I thought everyone knew that-
Doctor: [laughs] Are you a doctor?
- The Sledge Hammer!! punchline.... Trust me. I know what I'm doing.
- Invoked on Whose Line Is It Anyway?. The game "Two Line Vocabulary" involves two actors only allowed to say two things each, intended to wear out The Straight Man of the act. Ryan gets the line "Don't Worry, I'm A Doctor", which gets repeated to a hilarious extent.
- Inverted in The Blacklist when Keen first meets Reddington.
Keen: And I'm supposed to believe you?Reddington: (laughs) Of course not. I'm a criminal. Criminals are notorious liars.
- In Dead Rising, after Larry Chiang sticks Carlito on a meathook, he assures to Frank, "Trust me, I'm a butcher."
- In The Adventures of Dr. McNinja, Dr. McNinja feels it is important every once in a while to remind people who are having discussions with him that he's a doctor, even while arguing with Death.
- In the very first strip of Skin Horse: "The situation is under control. I'm a psychologist."
- In 8-Bit Theater, the justification that Red Mage often uses for whatever stupid plan that he has is his supposed status as a "fractactical genius".
- Penny Arcade: "It's okay, I'm a dentist."
- Whenever Something Awful cracks jokes about Ron Paul, the sentence "I'm a doctor," or a close variant, tends to show up as a joke reason for why his political platform should be taken seriously.
- The online blog Trust Me, I'm a Doctor
- Cross-over with Memetic Mutation: Don't worry, I'm/we're from the Internet
- A "Dr. Cairo" made a statement along these lines on Twitter while talking to Noah of Tribe Twelve, despite previously establishing that he's a student.
- In a Ruby Quest spin-off, "Deja vu Ruby Quest", Filbert gets Ruby before she can even react, and keeps telling her not to worry, even if he has a bonesaw in a hand and a scalpel in the other. If it counts as canon, this spin-off was before Ruby Quest's beginning, so Filbert still has his right hand.
- Catface likes to give strange advice and reassure the viewer with his unofficial catchphrase, "Trust me, I'm a cat!" However, he also inverts this saying, "I don't know, I'm a cat!"
- In the tgchan adventure The Sunfish, a flashback shows the protagonists as kids. Young Sam insists she's a doctor (mentioning the title phrase to young Annie) due to her implanted memories of Dr. Tran.
- Family Guy gave us "Relax, I be a doctor." Scary.
- Another episode includes Quagmire faking a heart attack to get out of an unwanted marriage. When he collapses, Joe (who was in on the plan) checks his pulse and announces, "He's dead. I know, I'm a cop."
- In American Dad!, Roger does this all the time. One particular example includes his attempt to massage Steve's ex-girlfriend, who Roger had a crush on at the time, while insisting, "Don't worry, I'm a licensed chiropractor, or whatever."
"Don't worry, I'm a whale biologist."
- Dan Vs.: Hilariously inverted in "Dan Vs. The Animal Shelter".
Doctor: Okay, let's get those pants off.Dan: Um... I'm here about my face being all scratched.Doctor: (chuckles) Oh, don't worry. I'm not a doctor.
- Ratchet of Transformers: Prime gives us this line just before proceeding to open up a can of whup-ass while experiencing the Autobot equivalent of roid rage:
"It's all right, I'm an emergency vehicle."
- The title of a cassette tape published by Dr. Joel Wallach, who does entertaining and controversial seminars about the benefits of vitamin and mineral supplements in nutrition, was Trust Me, I'm a Doctor.