This list covers all minor criminals mentioned in Season Six.
The Longest Night
Nora Flynn
A drug-addicted prostitute and the mother of serial killer Billy Flynn, Nora would put her son in the closet whenever she had a client over and sometimes even allowed them to sexually assault him. Despite this, they sometimes danced together. Finally snapping at age 13, Billy killed her and a client named John in 1968.
Compromising Positions
Bob Atkins
A man who was fatally shot with a silenced 9mm pistol, whose death remained unsolved. He was suspected of being the father of a child whose mother was the wife of James Thomas.
James Boyd
A man who was fatally shot with a silenced 9mm pistol, whose death, much like Bob Atkins, remained unsolved. Like Atkins, he was also suspected of being the father of a child whose mother was the wife of James Thomas.
Unnamed silenced 9mm killer
A man who fatally shot another unidentified man with a silenced 9mm pistol. The case remains unsolved. The victim was suspected of being the father of a child whose mother was the wife of James Thomas.
Middle Man
Michael Kosina's previous accomplices
The accomplices of then-serial rapist Michael Kosina in northern Louisiana, who both disappeared after being killed by Michael himself following a series of rapes in the area. The police pinned the crimes on them as a result until Michael's death.
What Happens at Home
Charles Beauchamp
A serial killer in North Dakota known as "The Redmond Ripper", Charles Beauchamp is the father of FBI cadet
Beauchamp
Ashley Seaver. When she was a child, he killed 25 women over the course of 10 years. His nickname suggests their deaths were very brutal and bloody. He was extremely protective of his daughter and was terrified of letting her out of the house because he knew there were more men like him outside. He tried very hard to be a good father and would give her all the toys she wanted, though he refused to have any pets in the house because he knew he couldn't control his homicidal urges around them. When a young Seaver brought home a puppy she wanted to care for one day, he killed the puppy with the argument of they "didn't need another mouth to fee".
In the end, he was arrested by Rossi and Hotch. He would later say it was the best day of his life as it meant he no longer had to hide and wouldn't hurt anyone else. Because of that statement, it is possible that his killings, or at least a portion of it, were acted out of compulsion. He is currently in prison, since North Dakota doesn't have capital punishment, and is very likely serving a life sentence with no possibility of parole. He sometimes writes to Seaver, though she never reads his letters.
Beauchamp appears to be based on Keith Hunter Jesperson - Both are serial killers with a daughter, practiced animal cruelty in front of their daughters, targeted women, were given nicknames from their crimes, and their daughters would go on to change their names and live successful lives.
Corazón
Hollis Walker, Sr.
The father of serial killer Hollis Walker, the senior Walker was an expert on indigenous African religions who was highly abusive towards his son, to the point where he didn't bring him back home from boarding school even after his wife and the younger Hollis' mom committed suicide, leaving Hollis to stay at school even during vacations and school breaks. After the younger Walker also became a professor of indigenous African religions as an adult, Hollis Sr. wrote a negative review of a book he wrote, which became a catalyst in Hollis Jr.'s murders.
Los Machetes
A Miami street gang mentioned in the episode. Its signature was cutting off the arms and heads of their victims with machetes, hence the name. Julio Ruiz was a member of Los Machetes in his youth.
The Thirteenth Step
Paul Donovan
The alcoholic father of sociopathic spree killer Raymond Donovan. When Ray was seven, Paul molested his son, presumably while he was drunk, and Ray was traumatized ever since. An adult Ray tracked Paul down in Idaho during his killing spree with his wife Sydney Manning, held him and his own wife hostage, and played a game of Russian Roulette with him in order to get him to confess to the molestation and make amends. When Paul repeatedly and vehemently refused, denying the molestation ever occurred, an impatient Sydney shot him through the forehead, killing him instantly.
Gary Manning
The father of psychopathic spree killer Sydney Manning, who owned a gas station. He was a pedophile who repeatedly molested his daughter as a child, sometimes while at work. The molestation shaped Sydney's psychopathic tendencies as a result. When an unknown event placed Sydney in foster care in Billings, Montana, Gary moved on and married another woman named Karen, having a daughter named Heather with her.
For some unknown reason, he decided to change his pedophilic ways and became a devoutly religious man, never sexually abusing Heather even once. An adult Sydney tracked him down in Spokane, Washington, during her killing spree with her husband Ray, held him and Heather hostage, and beat him despite his pleas that he had changed and that he never hurt Heather. An unconvinced Ray took him to a back room and fatally shot him.
With Friends Like These...
Benjamin Hadley
A resident of an apartment complex in which the unsub claimed another victim, Hadley shot a cleaning man in the genitals when he learned that his wife was sleeping with him. It is unknown if the victim survived.
Hanley Waters
Hanley Waters
A man who robbed a liquor store on April 6, 2010, and subsequently led the police in a high-speed car chase. The chase ended abruptly when he collided with a car driven by future spree killer Shelley Chamberlain, killing her son Damien, who was celebrating his sixth birthday that day. He was later arrested and incarcerated for his crimes. Waters was also responsible for the death of a police officer named Scott Jarand, who was killed instantly in another collision, which made headlines.
Out of the Light
Sam Edmann
A sex offender convicted of fondling his girlfriend's six-year-old son.
Mark Hillman
A sex offender convicted of flashing a woman.
Big Sea
John Hitchens
A coworker of Morgan's cousin, Cindi, who began stalking her in 2004. Though they only went on one date and shared one goodnight kiss, he started calling her constantly and sending her gifts that she returned. Ultimately, his stalking became so severe that she fled the state and went to Charleston. She did so on Morgan's advice, as he knew Hitchens was a power-assertive stalker and that it would most likely end badly if the stalking continued.
Two weeks after Cindi disappeared, Hitchens was shot and killed by Malcolm Ford, a man also stalking Cindi who made it look like a suicide. At the time, the police figured Hitchens had killed Cindi, though there was no body. However, this was eventually proven to be false on the episode's follow-up, The Company.
Chuck Wells
The father of serial killer Blake Wells, Chuck worked as a fisherman and was an abusive alcoholic. He later abandoned his wife and son after the former was diagnosed with breast cancer in October 1998 and moved to Norfolk, Virginia. After his wife died in January 1999, Chuck reclaimed Blake and forced him to work at a fish cannery, keeping the paychecks he earned and spending them on alcohol. One day, Chuck hit Blake so hard his arm broke. Regardless, he forced his son to work until he passed out. Finally snapping one day, Blake tortured and killed Chuck, dumping his body in the ocean.