Shawn: I gave you the guy!
Detective Lassiter: He had a partner.
Shawn: I have to find that guy now? I'm confused; when do you start chipping in?
Character with no formal connection to law enforcement who regularly solves crimes but does not get paid for it.
Often a Mystery Magnet. If so, despite the amazing number and variety of murders that occur wherever he or she happens to be, the Amateur Sleuth is rarely—if ever—suspected of any complicity. This notwithstanding, the possibility that the Amateur Sleuth is in fact a very clever serial killer is a common joking assertion among some viewers. As one stand-up comedian once said of Jessica Fletcher from Murder, She Wrote, "Wherever dat little white woman goes, somebody dies!" Another stand-up comedian remarked that "giving this woman a plane ticket is like giving Manson parole."
The other variety of amateur sleuth acts just like a professional, apart from the minor details of not having police powers, and not being paid to solve crimes. Intrepid Reporters generally fall into this category. This might include a sleuth that would plausibly work with police on a regular basis because of the nature of their job. A typical example of this might be a district attorney or an insurance agent.
One common variety is a retired detective, such as Hercule Poirot or Nick Charles. Other specific varations are the Little Old Lady Investigates and the Kid Detective. Some Hardboiled Detectives will be amateur sleuths, though this is rare. Compare Private Detective.
In literature, amateur sleuths are very frequently Every Man (or more often Every Woman) characters who are neverthless, regarded as very intelligent and charismatic. They are not heroic in the I Was Born Ready sense but are still courageous and prefer brains to brawn (which they are unsuited for anyway). They are very much Mary Sue in that they can somehow inexplicably take center stage in solving the mystery. Often it occurs without the character actually stepping forward and assertively taking charge, but only because others simply defer to her because of her natural intelligence and intuition. The amateur sleuth genre is especially known for having a built in readership. One of the things often said about such readers is that they consider themselves more intelligent than the general public at large, and are typically not two-fisted alpha types such as those who commonly become heroes in fiction. There is the expectation from the readers that the protagonist be the type of character that they can see themselves as. Also, a good number of self published and small press mystery authors give their protagonists the same daytime profession as themselves.
- Shinichi Kudo from Detective Conan (Case Closed in the US), before he is turned into a schoolboy Kid Detective through a fictional drug.
- The series actually has several of those, starting with Shinichi's father Yusaku who used to be sleuth and then became a mystery novelist. The one we see the most is Shinichi/Conan's friend Heiji Hattori, the son of a high-ranked policeman who often helps his dad as well as Conan himself. And in fact, there's a short arc named Detectives Koshien which gathers Conan, Heiji, and other three school-aged sleuths (Saaaguru Hakuba, Junya Tokitsu, and Natsuki Koshimizu) for a TV competition between them. Which actually was a trap, since one of the detectives had greatly wronged another... and ended up dead for his trouble.
- And the aforementioned Saguru Hakuba is the Amateur Sleuth in another series by Gosho Aoyama, Magic Kaito.
- Subversion: Yagami Light in Death Note—although he used to be an amateur sleuth, he is now a very clever serial killer.
- Jotaro Kujo, of JoJo's Bizarre Adventure. The guy, as far as we know, has never taken a single class on the subject, but repeatedly outwits opponents and discerns the nature of the situation through intuition. Well, that and watching lots of Columbo when he was younger.
- The titular Psychic Detective Yakumo, a college student who can see dead people.
- Kyuu Renjou and his friends in Tantei Gakuen Q attend an academy for those.
- The Batman. 'Nuff Said.
- The Elongated Man, Ralph Dibney, also emphasizes detection in most of his stories (his name being a play on "The Thin Man"), separating him from the wackiness of Plastic Man (who he started as an Captain Ersatz of) and the grim, Goddamn-Batmanitude of Batman.
- Francis Albany and Olivia Sturgess.
- Rorschach from Watchmen.
- Really, every superhero who isn't officially authorized by the police or government.
- The Sandman; that is, the Golden Age Sandman, not the guy with the dark hair and pale skin.
- Aside from John Hartigan, every hero in Sin City fits this description since they are not normally professional detectives (although Dwight used to be a PI).
- Mickey Mouse, believe it or not. Building on traditions from the newspaper strip by Floyd Gottfredson, and the later Mickey/Goofy adventure comics by Paul Murry, Mickey often appears as an Amateur Sleuth in comics, in some stories even being presented as a liscenced private eye.
- Flavia Gemina and her friends in the The Roman Mysteries are KidDetectives and Amateur Sleuths in The Roman Empire.
- Agatha Christie's Miss Marple, an elderly woman.
- Margery Allingham's Albert Campion.
- Jack Reacher, the character Lee Child's Reacher novels are based around. A freelancing drifter who solves murders, and various other mysteries, living off a payout received at the end of his military days, and money obtained from bad guys or in gratitude for solving cases.
- Dorothy L. Sayers's Lord Peter Wimsey, an independently wealthy aristocrat whose hobby is detection; except for once moonlighting as an advertising copywriter, he has never held a job—he's too rich to actually need one.
- Dorothy L. Sayers also wrote a number of short stories featuring a traveling salesman with the unlikely name of Montague Egg; when he's not acting in his capacity as a broker for a London firm of wine merchants, he finds himself occasionally stumbling across crime scenes and offering his common-sense expertise.
- Nancy Drew, a schoolgirl.
- The Hardy Boys, schoolboys. (Subverted in the 3rd season of the 1970s tv series in which the Boys so impressed a Justice Department official that they are recruited as professional agents for the organization).
- The priest Father Brown, in the Father Brown stories of G.K. Chesterton.
- Encyclopedia Brown, schoolboy.
- Lawrence Block's Bernie Rhodenbarr is a professional burglar who has a habit of running across murders during his "jobs" - and usually ends up the prime suspect, forcing him to solve the cases in order to exonerate himself.
- Ellery Queen, created by Frederic Dannay and Manfred B. Lee under the pseudonym "Ellery Queen," is a mystery writer who assists his police chief father on tough cases.
- The duo also created Shakespearean actor Drury Lane, who took up detecting as a hobby after retiring from the stage.
- The Happy Hollisters, a family with five children.
- Although the Trope Codifier Sherlock Holmes has no formal connection to law enforcement and is occasionally referred to as an "amateur" in the stories, he doesn't quite fit this trope since crime-solving is still his primary line of work. And he gets paid for it.
- He is professionally termed as a "Consulting Detective" and charges fees for his services. He would appear to be what we'd commonly call now a private investigator.
- Holmes describes himself as an "amateur of crime", using the term in the then-current usage to mean an enthusiast or "lover" of crime, from the latin "amo". He does refer to "remitting his fees entirely" at his discretion, and does so on at least one occasion; there are also occasions where he does not actually solve the crime - the murder of Charles Augustus Milverton, for example, where he colludes in covering the matter up - or there IS no crime, such as "The Man With The Twisted Lip".
- He is professionally termed as a "Consulting Detective" and charges fees for his services. He would appear to be what we'd commonly call now a private investigator.
- Amelia Peabody and her husband Radcliffe Emerson are both amateur sleuths who are both Victorian Egyptologists, so that they qualify for Adventurer Archaeologist, not to mention Battle Couple.
- Ellis Peters' Brother Cadfael.
- Charles Paris, a perennially semi-employed British actor, in a series of books by Simon Brett. He's usually a suspect at some point.
- Nicholas Bracewell, "bookholder" (stage manager) for an Elizabethan theater company, in a series by Edward Marston.
- Groucho Marx, Master Detective, by Ron Gulart.
- Sujata Massey's Rei Shimura is a Japanese-American antique dealer/amateur sleuth. In later books of the series, however, she becomes an official agent for a CIA-wannabe.
- The Boxcar Children, although being a series aimed at young children, the "crimes" they solve are rarely very serious.
- Half Moon Investigations, written by Eoin Colfer, involves Fletcher Moon who is a 12-year-old detective. Somewhat of a subversion in that Fletcher is a certified Private Eye, but he is certified in the US and lives in Ireland. (He took an online course.)
- John Dickson Carr's portly master detective Dr. Gideon Fell, and (under the pseudonym Carter Dickson) Sir Henry Merrivale, the masters of the locked room murder.
- John Putnam Thatcher, written by Emma Lathen (pseudonym for the writing partnership of Mary Jane Latsis and Martha Henissart), is a Wall Street banker. Supposedly the two chose a banker as their detective because "there is nothing on God's earth a banker can't get into". (Though, if they'd been writing after the banking crisis/recession instead of before .... )
- Irwin Maurice "Fletch" Fletcher, from Gregory McDonald's series of Fletch novels. As far as I can remember, he was only ever suspected in Confess, Fletch, and even then not seriously; for five of the books he's a an Intrepid Reporter but about halfway through the series goes into semiretirement and is just the guy who happens to be there.
- Brother William of Baskerville from The Name of the Rose.
- TKKG from the series of the same name. A group of kids doing investigations.
- Simon Rattray (Elleston Trevor) wrote a series of mysteries with chess-themed titles about Hugo Bishop. The back covers of the 1980s editions all carried the words, "He's not a cop, nor a private eye. He just shows up to help." He's noted as writing books collectively titled Personality Under Stress, which suggests some sort of psychologist, but he's accustomed to things like finding a bomb in his airplane. He's on a First-Name Basis with a Scotland Yard inspector (they're old school chums), and a number of other policemen recognize him with a respectful, "Oh, it's you, Mr. Bishop," and take his orders without much question.
- The main character of Sarah Caudwell's Hilary Tamar books is an Oxford professor, who is assisted in solving crimes by a quartet of barristers.
- Trixie, Honey and their friends in the Trixie Belden series.
- Kate Appleton from Janet Evanovich's Love in a Nutshell
- Fisk and Michael in the Knight and Rogue Series.
- Jessica Fletcher, a crime author, in Murder, She Wrote.
- Dr. Mark Sloan, a surgeon, in Diagnosis: Murder, which is also blended with the Medical Drama.
- Jonathan Creek, a magician's assistant who solves impossible crimes, including the occasional Locked Room Mystery.
- The Harts (a self-made millionaire and a journalist) in Hart to Hart.
- The titular OCD and phobia-ridden detective of Monk does have a somewhat official connection to law enforcement, but murders do happen wherever he goes, which means he's often outside SFPD jurisdiction.
- Before that he was already solving crimes since junior high.
- The Winchesters on Supernatural. Their only connection to the law consists of constantly being on the run from it, though occasionally they stumble onto a sympathetic detective who at least doesn't turn them in right away.
- As a recent example, Dexter, whose adopted father and sister are both official law enforcement officers, but he works only as a technical consultant. It may be interesting to note that in this series, the amateur sleuth actually is a clever serial killer, although his skill at hiding his murders means that he is rarely called to investigate his own crimes. Except, of course, in the second series, when a scuba diver stumbles onto Dexter's underwater burial ground, and the central plot is about the hunt for the "Bay Harbor Butcher" (Dexter) and Dexter's attempts to sabotage the investigation and not get caught.
- The UCOS squad of New Tricks is composed of retired detectives who, although they investigate unsolved crimes, are not actually official police officers. They actually use this, though, in order to bend the rules that would otherwise constrain serving officers (much to the displeasure of their boss, who is a serving officer).
- The titular character of Veronica Mars starts out as a semi-amateur sleuth, in that she helps out her father with his case load as a PI while at the same time carrying on her own investigation into her best friend's death (effectively pro bono, as the case is considered solved by the law). Towards the end of the first season, she becomes an unlicensed PI to many of her fellow high school students, digging up information in exchange for cash. In the third season, legally an adult, she passes her test to become a licensed PI. The proposed fourth season which never got off the ground would have ended the amateur part completely, jumping ahead a couple of years for her to become an FBI agent.
- Angel similarly starts off as a vigilante, eventually branching out into paranormal (and unlicensed) PI work where he sometimes is and isn't paid. The more personal work that becomes the Story Arc for the season is usually free, while the Monster of the Week case often ends up with money changing hands. In the third season, with the birth of his son, he becomes money-obsessed for a short time. This is mostly abandoned by season 5, when he and his group take over Wolfram & Hart's LA branch.
- Father Dowling of the Father Dowling Mysteries.
- Ned in Pushing Daisies is the assistant to a private detective, but his proper job and true passion is baking pies.
- Chance Harper of Strange Luck often wound up in a position to solve crimes, albeit more because of his role as an all-around Weirdness Magnet than a Mystery Magnet. Subverted in that he was just as likely to be in a position to get blamed for a crime he'd have gladly played no part in solving. A freelance photographer by trade, figuring he may as well sell photos of the bizarre shit that's always happening to him.
- John Smith, the hero of the TV version of The Dead Zone, is just a retired schoolteacher (with lots of money) who's driven to solve crimes and prevent disasters because of the visions he starts getting after waking up from a six-year coma. In the pilot, however, he develops an extremely useful law enforcement connection in the form of his ex-fiancee's new husband, who also happens to be the local sheriff. Throughout the series (until Sheriff Bannerman dies) they constantly trade favors and help each other with their cases.
- Jonathan on Bored to Death. (He's not good at it.)
- Mystery writer Richard Castle. (He's very good at it.)
- Shawn Spencer on Psych originally just used the deduction skills his father taught him since childhood to simply call in tips for the reward money. The police, however, believed from the amount of good info he provided, that he was involved in the majority of crimes he helped solved. Before Shawn can be arrested as an accomplice, he fools them by proclaiming he has psychic abilities. Now to keep the ruse going, Shawn with the help of his best friend Gus must continue aiding the police in various investigations as a paid "psychic consultant".
- Charlie Eppes on Numb3rs. Plausibly justified in his case.
- Charlie is employed by the FBI as a consultant and he got his start by accident when his FBI agent brother was working a serial killer case. Charlie developed a system that would predict where the killer lives based on where the victims are killed after seeing a map of the locations. He also has sufficient security clearance given his past work with the NSA, which was sufficiently classified that his brother didn't know.
- Cal Lightman and his staff on Lie to Me are psychologists specializing in discerning whether or not someone's telling the truth. The police and FBI frequently find this useful.
- Subverted by Patrick Jane on The Mentalist. He checks all the boxes on the Amateur Sleuth checklist - former conman using his skills at getting inside the minds of criminals and suspects to crack cases that leave trained detectives stumped - except that he's actually on the police payroll as a consultant.
- Shirley from The Adventures of Shirley Holmes. Of course.
- Perry Mason and Ben Matlock, attorneys for the defence; famous for The Perry Mason Method of sleuthing.
- In the Community episode "Theories and Interior Design" Annie becomes one, drawing a very reluctant Jeff into her investigation of Professor Professorson.
- Hardy Boys-Nancy Drew Mysteries: No matter where Frank & Joe Hardy go, they end up involved in a mystery...though the show sometimes subverts it by having the cops or others get real suspicious about the Hardys' involvement, up to and including tossing them in jail.
- Pennington of Paper Mario: The Thousand-Year Door certainly acts the part, but he may be one of the worst amateur sleuths on the face of the planet. He spends the entire sixth chapter of the game trying to solve one mystery after another with Mario's "help", and gets every single possible thing wrong, even when the answer is right in front of his face. He even mis-guesses the identity of his "deputy" (admittedly, he wasn't too far off on that last one. He guesses Luigi).
- Robert Cath, protagonist and player character of the adventure game The Last Express, boards a train to find his friend murdered, and proceeds to investigate both the murder and various pieces of international intrigue aboard.
- In a more obscure example, The Learning Company's Super Solvers edutainment games.
- Jake and Jennifer Eagle of the Eagle Eye Mysteries Edutainment Game series.
- The four kids in The Clue Finders Edutainment Game series in a couple of the games.
- The main cast of Persona 4. However, they're not very good at actually solving the case, and it isn't until a actual detective joins the group that they start making headway.
- The Ace Attorney series runs on this; both Phoenix and Apollo tend to do most of the detective work for their clients despite being defense attorneys with no police training. The games don't seem to be sure if this is legal or not within the game world.
- And in Ace Attorney Investigations Prosecutor Edgeworth does no prosecuting but a lot of detective work. In fact, the Judge lampshades this at the end of the game.
Judge: A prosecutor joined forces with a thief and became a detective. Maybe I should join forces with a bailiff and become a lawyer!
- In Umineko no Naku Koro ni, Furudo Erika is one. Or believe to be one, anyway. Battler would count as well, had he actually solved anything.
- The main character in the Murder Mystery Visual Novel Jisei, who is accused of committing murder, helps question possible suspects in the vicinity of the crime so that he may clear his name and assist the detective on the scene in finding the real killer.
- El Goonish Shive got Ellen & Nanase, who investigate weirdness together and have numerous fans. Diane can be pretty good at reading people, noticing and puzzling out the details… when she's actually paying attention, but doesn't chase weird cases unless roped into it by someone she likes. And her roommate Charlotte is an "aficionado of spooky things" (which are not scarce in Moperville) and sort of fan of Ellen & Nanase too. So after their first adventure together they jokingly called themselves "Charlotte's Angels" and then she invited them again.
- Freefall got a team of Sawtooth Rivergrinder (a terraforming robot) and Florence Ambrose (who as a humanoid uplifted wolf, can both pick up scents and explain what she noticed). Another robot even gifted Sawtooth a "detective hat".
- The Whitman Literary Girls, in the Whateley Universe. Some of them also write (bad) detective stories for the others to read.
- Fletcher (and the future Intrepid Reporter George) in the Internet Deconstruction of the noir genre B.J. Fletcher: Private Eye is a surprisingly effective Amateur Sleuth.
- Andrew "Lucky" Starr from the Global Guardians PBEM Universe doesn't actually go out looking for mysteries to solve. He's just lucky that way.
- Ryney at The Mystery Sphere. He doesn't really want to solve anything, he's just too lazy to argue against solving things.
- Peter R. De Vries, crime reporter. Cracked more cases than Detective Conan (and he's a cartoon character). Though in real life this means tracking down petty swindlers in most cases. But his big cases include tracking down the big bad of the beer-brewing billionaire kidnappers, getting two innocent people accused of murder out of jail and catching the real killer, foiled a prince and princess any rights to the throne as the princess had a prior relationship with the biggest drug lord in Dutch history and tricked a sociopath to confess on hidden camera the murder of a missing girl in Aruba, whom he also caught trafficking Thai prostitutes a few months earlier.
- Dr. Clifford Stoll was an astronomer and sysadmin who traced a 75 cent accounting dependency to a KGB sponsored hacker in Germany trying to steal nuclear secrets after the FBI, CIA, NSA, and Air Force OSI couldn't be bothered due to the small size of the finical theft or jurisdiction issues. He kept extensive logs of his work which he used to write a book, The Cuckoo's Egg, chronicling his investigation and making it one of the first documented counter-hacker efforts. (Dr. Stoll also wrote books about how E-commerce and online news will never happen. No one is perfect.)
- The vast majority of spies(including law enforcement ones as well as interstate politics ones) tend to be recruited from people who do not make an official career in spying in the sense of being trained members of an agency, but who are for some reason on the spot and willing or compelled to do the job.