Can't wait for Orange is the New Black's fourth season ? We don't blame you; Netflix's prison comedy is as great as ever. In the most recent season, we learned even more about how the characters end up at Litchfield through flashbacks. In case you missed anything, here's the definitive guide to exactly what each inmate did wrong — besides get caught, obviously.
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In season three, it's revealed that Leanne was part of an Amish community before she heads to Litchfield. She left her family and got into drugs with a bad crowd, but decided to return. She made the fatal mistake of leaving her backpack filled with incriminating stuff near the outskirts of the town, and the police hauled her in. Leanne made a deal, agreeing to turn on her old friends and wear a wire.
As a young woman, Norma fell in love with a charismatic cult leader. Decades later, all his other wives have left him and she's the only one still standing. Though she was still optimistic about their potential, he screamed at her and insulted her intelligence. She promptly pushed him off a cliff, killing him.
Carrie "Big Boo" Black
Though we've seen flashbacks of Big Boo as a child, the precise nature of her crime is unknown. We do know she ran a gambling ring and she refers to herself as a "thieving dyke" on season three, so it may have something to do with stealing.
Watson was a talented track runner in high school, but her speed didn't make her very popular with boys. She was rejected by the cool crowd and started hanging out with some thugs. Together, they rob a store and Watson was arrested when she purposely slowed down while running from the cops.
Galina "Red" Reznikov
It's not completely clear what exactly lands Red in prison, but we do know that she and her husband owned a restaurant and that Red became involved with the Russian mafia. She punched one of the mob wives in the boob and ruptured an implant, but her solid business advice to the husband allowed her to stick around.
So far, Poussey's crime is unclear. What we do know about her past is that she lived in Germany, where her father was stationed with the US Army. She had a romantic relationship with the base commander's daughter, and this is what got her family reassigned to the States.
While we first assume Morello is planning her wedding  to her fiancé, Christopher, it's revealed that Christopher is the man she was stalking. After meeting at a post office, they went on one date, and she proceeded to stalk him. Eventually, she planted an explosive device in his actual girlfriend's car, attempting to murder her. She's still highly delusional about the nature of their relationship.
Tasha "Taystee" Jefferson
So far we just know that Taystee was involved in a drug ring run by Vee.
We don't know the details of Gina's crime, but it's been implied that murder and embezzlement play a part.
On season two, we learn that Gloria has a complicated background with domestic abuse and was arrested for food-stamp fraud.
Tiffany "Pennsatucky" Doggett
Pennsatucky is sent to Litchfield for shooting an abortion-clinic worker. Though it's assumed this is because of her serious religious beliefs, it's revealed that she shot the woman for making a remark about this being Pennsatucky's fifth abortion. Needless to say, Pennsatucky doesn't react well to being disrespected.
Yoga Jones is in the pen for killing a child. She used to be a marijuana farmer, but one day she mistook a child for a deer and shot the boy.
Marisol "Flaca" Gonzales
Flaca's crime is essentially being too smart. She started selling fake drugs at her school, but one of the kids to whom she sold the drugs thought he was really high and committed suicide by jumping off the roof of the school. She was arrested for fraud and endangerment.
Brook lands in prison due to some illegal political activism.
Suzanne "Crazy Eyes" Warren
We don't know what Crazy Eyes' crime is yet, but we do know about her background. She was adopted by a white, suburban couple, and despite loving her daughter, Crazy Eyes' mother often pushed her to accomplish more than she was comfortable with — like singing a song at her graduation.
Nicky is a former heroin addict who was raised by a wealthy but mostly absent mother. She is arrested for stealing a taxi with her friends so that she can get to her dealer in time to get drugs for the weekend.
Ten years before she landed in prison, Piper helped her then-girlfriend, Alex Vause, smuggle drug money during an extended vacation in Europe.
Dayanara "Daya" Diaz
Daya's exact crime is unknown, but we can assume it's drug-related. She grew up in an abusive environment with her mother, and at one point she slept with her mother's drug-dealer boyfriend to spite her mother.
Years ago, Sophia was a male fireman. Once she decided to transition to a female, she committed credit card fraud to finance her operation and hormone therapy. We also know that it was her son, who was having trouble with her transition, who turned her in.
Alex used to be a smuggler for a major drug cartel. Though she loved Piper, she also used her as a pawn in her smuggling operation. Ten years after the crime, Alex named Piper as an accomplice, and the two both ended up at Litchfield. She's still plagued by thoughts that her former boss may send someone to come after her.
Aleida (Daya's mother) used to be involved in a drug operation. Her boyfriend had her cutting and bagging drugs in her home, and she takes the fall for him.
Miss Claudette Pelage
Miss Claudette grew up as an illegal child laborer. She was sent to the United States to pay off a debt for her family, and when she grew up, she ran a cleaning service using illegal child labor. It's not clear whether she's in prison for this or because she beat a man to death for abusing one of her "employees." It's probably both.
"Black" Cindy Hayes
Cindy used to be the world's worst airport security employee. She would regularly harass and steal from travelers, and though it's not explicitly said that this behavior led to her arrest, it can be assumed.
Miss Rosa Cisneros
Back in the day, Miss Rosa was a pretty serious bank robber. She was good at stealing money, but she was cursed. Her crew of men dwindled as she would take one as her lover before he inevitably ended up dead by the end of the robbery. Eventually, she got caught.
A nun since young adulthood, Sister Ingalls became really involved in social activism. This continued throughout her career with the church, even publishing a book called Nun Shall Pass. Due to her growing hubris, the church refused to support her any longer, and she was arrested after handcuffing herself to a flagpole at a nuclear test site.
It's not explicitly explained, but one might assume Vee's imprisonment has to do with the drug ring she ran on the outside.