Crime The 'Grim Sleeper': 5 Things to Know About Serial Killer Lonnie Franklin Prosecutors say Lonnie Franklin Jr. is a serial killer who stalked Los Angeles, killing multiple women, and he has been dubbed the "Grim Sleeper" By Christine Pelisek Published on December 26, 2016 10:59 PM Share Tweet Pin Email This case was featured on Monday night’s People Magazine Investigates. Now learn more with PEOPLE’s complete digital coverage. The victims were all young vulnerable black women who lived in south Los Angeles and struggled with drug addiction. Their naked or partially clothed bodies were all dumped in the filthy neighborhood alleyways, left to rot under garbage and debris. They were shot at close range with a .25-caliber pistol, or strangled, or both. For years, their cases lacked justice — or even an arrest. But in May, following three months of testimony in Los Angeles Superior Court, Lonnie Franklin Jr., the “Grim Sleeper” serial killer who prosecutors say stalked L.A. for more than 20 years, was found guilty of murdering 10 women. Franklin was also found guilty of the attempted murder of Enietra Washington, who testified that he shot her, sexually assaulted her and took a Polaroid picture of her before pushing her out of his car 27 years ago. Franklin has since been sentenced to death. Here are five things to know about his case. 1. Prosecutors Say Franklin Is a Sexual Predator At his murder trial, prosecutors painted Franklin, a former corporal in the United States Army, as a sexual predator who killed women who “weren’t submissive enough.” “These crimes were about power and control,” prosecutor Beth Silverman told the jury during her closing arguments. “It is clear the defendant got pleasure from killing these young women because that’s how they all ended up,” Silverman said. “He definitely wanted to degrade these women by dumping their bodies like trash. He got off on that too and that is why he did it over and over. It gave him gratification.” • Related Story: How Reporter Christine Pelisek Helped Catch a Serial Killer AP Pool/Nick Ut,Pool 2. Franklin Allegedly Bragged About His Sexual Conquests Franklin’s longtime friend Ray Davis testified that Franklin’s conquests were a common topic of conversation between them. Franklin took photos of various women and joked that he had names for all the girls in the photos depending on what their breasts looked like, Davis told the jury. He also said that even though Franklin didn’t smoke marijuana, he kept a supply on hand for his various girlfriends. • Watch our new true crime show, People Magazine Investigates, which continues on Mondays at 10 p.m. ET on Investigation Discovery. 3. Franklin Was Convicted This Spring Franklin was convicted in May of the murder of 10 women — Debra Jackson, Henrietta Wright, Mary Lowe, Bernita Sparks, Barbara Ware, Lachrica Jefferson, Monique Alexander, Princess Berthomieux, Valerie McCorvey and Janecia Peters — and the attempted murder of another during a 23-year murder spree that began in 1984. Franklin’s last victim was 25-year-old Peters on Jan. 1, 2007. His youngest victim was Berthomieux, a15-year-old runaway, who was found strangled in an alley in Inglewood, California, in 2002. The apparent gaps in his violent slayings, from the late ’80s to early ’00s, led to his nickname. 4. Police Arrested Franklin After Years of Investigation — Via DNA Evidence The murder spree stumped detectives for more than two decades, and it wasn’t until the Los Angeles Police Department started its cold case unit that authorities realized the killer of seven women in the ’80s was linked through DNA and ballistics to deaths in 2002, 2003 and 2007. However, the killer’s DNA profile was not in CODIS, the national database for DNA. Franklin was finally caught in July 2010 through familial DNA testing after his 28-year-old son, Christopher, was arrested for carrying a weapon in the summer of 2009 and had to give up a DNA swab. • Related Story: How the Grim Sleeper Got His Nickname Once it was determined that Christopher was related to the killer, detectives followed the elder Franklin to a pizza place in Buena Park. As Franklin finished his meal, a detective who posed as a busboy collected a fork, two plastic cups, a plate and a pizza slice left by Franklin. A few days later, DNA taken from the pizza slice came back as a match to DNA. 5. Authorities Allegedly Found ‘Souvenirs’ of Victims in Franklin’s Home During the three-day search of Franklin s property, investigators allegedly found women’s necklaces, rings, earrings and watches as well as more than 500 photographs of various women — many of them naked or engaged in sex acts. In one of Franklin’s bedrooms, criminalist Rafael Garcia discovered a F.I.E Titan .25-caliber semiautomatic handgun, otherwise known as a “pocket pistol.” It was later determined to be the gun used to kill Janecia Peters. • Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter. In a backyard garage, an LAPD firearms examiner found a Polaroid photograph of survivor Enietra Washington, who later testified against Franklin at his trial. Also found was a photo of Peters. In the same envelope, they also found the school identification card of 18-year-old Ayellah Marshall and the Nevada driver’s license of Rolenia Morris, 29. Both women had been reported missing in February and September 2005, respectively. Both women were last seen in the vicinity of Franklin’s home at 81st and Western Avenues. Their bodies were never found. People Magazine Investigates airs Mondays (10 p.m. ET) on Investigation Discovery.