Fritz Haarmann

On 12 October 1900, Haarmann was deployed to the Alsatian city of Colmar to serve in the Number 10 Rifle Battalion. Throughout his service, Haarmann earned a reputation among his superiors as an exemplary soldier and excellent marksman, and he would later describe his period of service with this battalion as being the happiest of his entire life. After collapsing while on exercise with his battalion in October 1901, Haarmann began to suffer dizzy spells, and was subsequently hospitalized for over four months. He was later deemed "unsuitable for [military] service and work" and was dismissed from military service on 28 July 1902.[12]

Discharged from the military under medical terms[13] described as being "probable" dementia praecox,[14] Haarmann was awarded a monthly military pension of 21 gold marks.[n 3] Upon his military discharge, Haarmann returned to live with his fiancée in Hanover, briefly working in the small business his father had established, before unsuccessfully filing a maintenance lawsuit against his father, citing that he was unable to work due to the ailments noted by the military. His father successfully contested Haarmann's suit, and the charges were dropped. The following year, a violent fight between father and son resulted in Haarmann's father himself unsuccessfully initiating legal proceedings against his son, citing verbal death threats and blackmail as justification to have his son returned to a mental institution. These charges were dropped due to a lack of corroborating evidence. Nonetheless, Haarmann was ordered to undertake a psychiatric examination in May 1903. This examination was conducted by a Dr. Andrae, who concluded that, although morally inferior, Haarmann was not mentally unstable.

With financial assistance from his father, Haarmann and his fiancée opened a fishmongery. Haarmann himself briefly attempted to work as an insurance salesman, before being officially classified as disabled and unable to work[15] by the 10th Army in 1904. As a result, his monthly military pension was slightly increased. The same year, his fiancée, while pregnant with his child, terminated their engagement, and according to Haarmann this was because he accused his fiancée of having an affair with a student. As the fishmongery was registered in her name, Erna Haarmann simply ordered her husband to leave the premises.[15]

For the next decade, Haarmann primarily lived as a petty thief, burglar and con artist. Although he did occasionally obtain legitimate employment, he invariably stole from his employers or their customers. Beginning in 1905, he served several short prison sentences for offenses such as larceny, embezzlement and assault. On one occasion when working legitimately as an invoice clerk, Haarmann became acquainted with a female employee with whom, he later claimed, to have robbed several tombstones and graves between 1905 and 1913 (he was never charged with these offenses).[16] Consequently, Haarmann spent the majority of the years between 1905 and 1912 in jail.[17]

In late 1913, Haarmann was arrested for burglary. A search of his home revealed a hoard of stolen property linking him to several other burglaries. Despite protesting his innocence, Haarmann was charged with and convicted of a series of burglaries and frauds. He was sentenced to five years' imprisonment for these offenses.[18]

Due to compulsory conscription resulting from the outbreak of World War I, Germany saw a shortage of available domestic manpower. In the final years of his prison sentence, Haarmann was permitted to work throughout the day in the grounds of various manor houses near the town of Rendsburg,[19] with instructions to return to prison each evening. Upon his release from prison in April 1918, Haarmann initially moved to Berlin, before opting to return to Hanover, where he briefly lived with one of his sisters before renting a single room apartment in late August 1918.[20]

The years following the loss of World War I saw an increase in poverty, crime, and black market trading in the Weimar Republic.

According to Haarmann, he was struck by the poverty of the German nation as a result of the loss the nation had suffered in World War I. Through his initial efforts to both trade and purchase stolen property at Hanover Central Station, Haarmann established several criminal contacts with whom he could trade in contraband property, and he immediately reverted to the criminal life he had lived before his 1913 arrest.[21]

Between 1918 and 1924, Haarmann committed at least 24 murders, although he is suspected of murdering a minimum of 27. All of Haarmann's victims were males between the ages of 10 and 22, the majority of whom were in their mid- to late-teens. The victims were lured back to one of three addresses in which Haarmann is known to have resided throughout those years. He is known to have killed upon the promise of assistance, accommodation, work, or under the pretense of arrest. At Haarmann's apartment, the victim was typically given food and drink before Haarmann bit into his Adam's apple, often as he was strangled.[28] Often this caused the victim to die of asphyxiation, but on several occasions Haarmann bit completely through his victims' Adams apple and trachea.[29] (Haarmann referred to the act of biting through his victims' neck as his "love bite".)[30][31]

The Leine River, into which Haarmann disposed of many of his victims' dismembered remains

All of Haarmann's known victims were dismembered before their bodies were discarded, usually in the Leine River, although the dismembered body of his first known victim had simply been buried,[32] and the body of his last victim had been thrown into a lake located at the entrance to the Herrenhausen Gardens.[33]

Haarmann typically kept his victims' personal possessions, for himself or for his lover, Hans Grans, or they were sold on the black market through criminal contacts both men had established at Hanover Central Station. However, the personal possessions of some victims were sold to legitimate retailers. In several instances, both Haarmann and Grans gave possessions belonging to various victims to acquaintances as gifts.[34]

Following Haarmann's arrest, rumors circulated that Haarmann ate the flesh of his victims, or sold it on the black market as pork or horse meat.[35] Although no evidence was ever produced to confirm these theories, Haarmann was known to be an active trader in contraband meat,[36] which was invariably boneless, diced and often sold as ground meat.[37] When asked where he obtained the meat, Haarmann sometimes said he had gotten it from a butcher named "Karl".[38] Haarmann initially resided in a hotel, before he and Grans lodged with a middle-class family.[39]

On 17 May 1924,[67] two children playing near the Leine River discovered a human skull. Determined to be that of a young male aged between 18 and 20 and bearing evidence of knife wounds, police were skeptical as to whether a murder had been committed or whether the skull had either been discarded in this location by grave robbers, or placed there in a tasteless prank by medical students. Furthermore, police theorized the skull may have been discarded in the river at Alfeld, which had recently experienced an outbreak of typhoid.[67] Two weeks later, on 29 May, a second skull was found behind a mill race located close to the scene of the earlier discovery. This skull was also identified as having been that of a young male aged between 18 and 20. Shortly thereafter, two boys playing in a field close to the village of Döhren discovered a sack containing numerous human bones.[68]

Two more skulls would be found on 13 June: one upon the banks of the Leine River; another located close to a mill in west Hanover. Each of the skulls had been removed from the vertebrae with a sharp instrument. One skull belonged to a male in his late-teens, whereas the other belonged to a boy estimated to have been aged between 11 and 13 years old. In addition, one of these skulls also bore evidence of having been scalped.[67]

For more than a year prior to these discoveries, rumors had circulated in Hanover about the fate of the sheer number of children and teenagers who had been reported missing in the city. The discoveries sparked fresh rumors regarding missing and murdered children. In addition, various newspapers responded to these discoveries and the resulting rumors by harking to the disproportionate number of young people who had been reported missing in Hanover between 1918 and 1924.[n 5]

On 8 June, several hundred Hanover residents converged close to the Leine River and searched both the banks of the river and the surrounding areas, discovering a number of human bones, which were handed to the police. In response to these latest discoveries, police decided to drag the entire section of the river which ran through the centre of the city. In doing so, they discovered more than 500 further human bones[69] and sections of bodies, many bearing knife striations, which were later confirmed by a court doctor as having belonged to at least 22 separate human individuals. Approximately half of the remains had been in the river for some time, whereas other bones and body parts had been discarded in the river more recently. Many of the recent and aged discoveries bore evidence of having been dissected—particularly at the joints. Over 30 percent of the remains were judged to have belonged to young males aged between 15 and 20.[70]

Suspicion for the discoveries quickly fell upon Haarmann, who was known to both the police and the criminal investigation department as a homosexual who had amassed 15 previous convictions dating from 1896 for various offenses including child molestation and the sexual assault and battery of a minor.[41] Moreover, Haarmann had been connected to the 1918 disappearances of Friedel Rothe and a 14-year-old named Hermann Koch (who had disappeared weeks prior to Rothe). Haarmann was placed under surveillance.[71] Being a trusted police informant, Haarmann was known to frequent Hanover Central Station. As he was well known to many officers from Hanover, two young policemen were drafted from Berlin to pose as undercover officers and discreetly observe his movements. The surveillance of Haarmann began on 18 June 1924.[72]

On the night of 22 June, Haarmann was observed by the two undercover officers prowling Hanover's central station. He was soon observed arguing with a 15-year-old boy named Karl Fromm, then to approach police and insist they arrest the youth on the charge of travelling upon forged documents. Upon his arrest, Fromm informed police he had been living with Haarmann for four days, and that he had been repeatedly raped by his accuser, sometimes as a knife was held to his throat. Haarmann was arrested the following morning and charged with sexual assault.[73]

Detectives search a stove inside Haarmann's attic room at 2 Rote Reihe

Following his arrest. Haarmann's attic apartment at No. 2 Rote Reihe was searched. Haarmann had lived in this single room apartment since June 1923. The flooring, walls and bedding within the apartment were found to be extensively bloodstained.[74] Haarmann initially attempted to explain this fact as a by-product of his illegal trading in contraband meat.[75] Various acquaintances and former neighbours of Haarmann were also extensively questioned as to his activities. Many fellow tenants and neighbours of the various addresses in which Haarmann lived since 1920 commented to detectives about the number of teenage boys they observed visiting his various addresses. Moreover, some had seen him leaving his property with concealed sacks, bags or baskets—invariably in the late evening or early morning hours. Two former tenants informed police that, in the spring of 1924, they had discreetly followed Haarmann from his apartment and observed him discarding a heavy sack into the Leine River.[76]

The clothes and personal possessions found at Haarmann's apartment and in the possession of his acquaintances were suspected as being the property of missing youths: all were confiscated and put on display at Hanover Police Station, with the parents of missing teenage boys from across Germany invited to look at the items. As successive days passed, an increasing number of items were identified by family members as having belonged to their sons and brothers. Haarmann did initially attempt to dismiss these successive revelations as being circumstantial in nature by explaining he acquired many of these items through his business of trading in used clothing, with other items being left at his apartment by youths with whom he engaged in sexual activity.[77]

The turning point came when, on 29 June, clothes, boots and keys found stowed at Haarmann's apartment were identified as belonging to a missing 18-year-old named Robert Witzel. A skull which had been found in a garden on 20 May[78] (which was not initially connected with later skeletal discoveries) was identified as that of the missing youth. A friend of Witzel identified a police officer seen in the company of the youth the day prior to his disappearance as Haarmann. Confronted with this evidence, Haarmann briefly attempted to bluster his way out of these latest and most damning pieces of evidence. When Witzel's jacket was found in the possession of his landlady and he was confronted with various witnesses' testimony as to his destroying identification marks upon the clothing, he broke down and had to be supported by his sister.[n 6]

Confession

Faced with this latest evidence, and upon the urging of his sister,[81] Haarmann confessed to raping, killing and dismembering many young men in what he initially described as a "rabid sexual passion"[81] between 1918 and 1924. According to Haarmann, he never actually intended to murder any of his victims, but would be seized by an irresistible urge to bite into or through their Adam's apple[21]—often as he manually strangled them—in the throes of ecstasy, before typically collapsing atop the victim's body. Only one intended victim had escaped from Haarmann's apartment after he attempted to bite into his Adam's apple, although this individual is not known to have reported the attack to police.[77]

All of Haarmann's victims' bodies were disposed of via dismemberment shortly after their murder, and Haarmann was insistent that he found the act of dismemberment extremely unpleasant; he had, he stated, been ill for eight days after his first murder.[82] Nonetheless, Haarmann was insistent that his passion at the moment of murder was invariably "stronger than the horror of the cutting and the chopping" which would inevitably follow, and would typically take up to two days to complete.[83]

To fortify himself to dismember his victims' bodies, Haarmann would pour himself a cup of strong black coffee,[84] then place the body of his victim upon the floor of this apartment and cover the face with cloth, before first removing the intestines, which he would place inside a bucket. A towel would then be repeatedly placed inside the abdominal cavity to soak the collecting blood. He would then make three cuts between the victim's ribs and shoulders, then "take hold of the ribs and push until the bones around the shoulders broke."[28] The victim's heart, lungs and kidneys would then be removed, diced, and placed in the same bucket which held the intestines before the legs and arms would be severed from the body. Haarmann would then begin paring the flesh from the limbs and torso. This surplus flesh would be disposed of in the toilet or, usually, in the nearby river.[85]

Fritz Haarmann (centre) with police detectives, November 1924

The final section of the victims' bodies to be dismembered was invariably the head. After severing the head from the torso, Haarmann would use a small kitchen knife to strip all flesh from the skull, which he would then wrap in rags and place face downwards upon a pile of straw and bludgeon with an axe until the skull splintered, enabling him to access the brain. This he would also place in a bucket, which he would pour, alongside the "chopped up bones" in the Leine.[36]

Haarmann was insistent that none of the skulls found in the Leine belonged to his victims, and that the forensic identification of the skull of Robert Witzel was mistaken, as he had almost invariably smashed his victims' skulls to pieces. The exceptions being those of his earliest victims—killed several years prior to his arrest—and that of his last victim, Erich de Vries.[32] Although insistent that none of his murders were premeditated, investigators discovered much circumstantial evidence suggesting that several murders had been planned hours or days in advance, and that Haarmann had both concocted explanations for his victims' disappearances and dissuaded acquaintances of his victims from filing missing persons' reports with Hanover police.[86] Investigators also noted that Haarmann would only confess to murders for which there existed evidence against him; on one occasion, Haarmann stated: "There are some [victims] you don't know about, but it's not those you think."[87]

When asked how many victims he killed, Haarmann claimed, "Somewhere between 50 and 70." The police, however, could only connect Haarmann with the disappearance of 27 youths, and he was charged with 27 murders—some of which he claimed were committed upon the insistence of Hans Grans,[88] who was arrested on 8 July, and formally charged with being an accessory to murder one week later.[89][n 7]

On 16 August 1924, Haarmann underwent a psychological examination at a Göttingen medical school; on 25 September, he was judged competent to stand trial and returned to Hanover to await trial.[32]

The trial of Fritz Haarmann and Hans Grans began on 4 December 1924. Haarmann was charged with the murder of 27[90] boys and young men who had disappeared between September 1918 and June 1924. In 14 of these cases, Haarmann—who insisted upon conducting his own defense—acknowledged his guilt,[83] although he claimed to be uncertain of the identification of the remaining 13 victims upon the list of charges. Grans pleaded not guilty to charges of being an accessory to murder in several of the murders.[91] Initially, following a thorough security search, all members of the public were permitted access to the courtroom, although by the third day[92] the judge excluded all spectators from the courtroom in the opening days of the trial as each murder was discussed in detail, due to the ongoing carnal and gruesome nature of the revelations.[47][93]

Hans Grans (head bowed) is escorted into court, December 1924

The trial was one of the first major modern media events in Germany, and received extensive international press coverage, being described as the "most revolting [case] in German criminal history."[64] Varying sensational headlines—in which Haarmann was variously referred to by such titles as the "Butcher of Hanover," the "Vampire of Hanover," and the "Wolf Man"—continuously appeared in the press.

Although Haarmann denied any premeditation in the crimes,[94] and remained adamant the ultimate reason he killed was a "mystery" to him,[47] he readily confessed to having killed 14 of the victims for whose murder he was tried and to retaining and selling many of their possessions, although he denied having sold the body parts of any of his victims as contraband meat.[83] Haarmann's denial that he had either consumed or sold human flesh would be supported by a medical expert, who testified on 6 December that none of the meat found in Haarmann's apartment following his arrest was human.[64]

When asked to identify photographs of his victims, Haarmann became taciturn and dismissive as he typically claimed to be unable to recognize any of his victims' photographs; however, in instances where he claimed to be unable to recognize his victims' faces but the victims' clothing or other personal belongings had been found in his possession, he would simply shrug and make comments to the effect of, "I probably killed him,"[93] or: "Charge it to me; it's alright with me."[95] For example, when asked to identify a photograph of victim Alfred Hogrefe, Haarmann stated: "I certainly assume I killed Hogrefe, but I don't remember his face."[96][n 8]

Numerous exhibits were introduced into evidence in the opening days of the trial, including 285 sections of the skeletal structure—particularly skulls and thigh bones[97]—recovered from the Leine River and forensically determined as belonging to young men under 20 years of age[98] which had been retrieved from the Leine River, the bucket into which he stored and transported human remains, and the extensively bloodstained camp bed upon which he had killed many of the victims at his Rote Reihe address.[64] As had been the case when earlier asked whether he could recognize the photographs of any of his victims, Haarmann's demeanour became dismissive upon the introduction of these exhibits; he denied any of the skulls introduced into evidence belonged to his victims, stating he had almost invariably "mashed" the victims' skulls, and had thrown only one undamaged skull into the river.[99]

Several acquaintances and criminal associates of Haarmann testified for the prosecution, including former neighbours who testified to having purchased brawn or mince from Haarmann, whom they noted regularly left his apartment with packages of meat, but rarely arrived with them. Haarmann's landlady, Elisabeth Engel, testified that Haarmann would regularly pour chopped pieces of meat into boiling water and would strain fat from meat Haarmann claimed was pork.[100] This fat would invariably be poured into bottles. On one occasion in April 1924,[35] Haarmann's landlady and her family became ill after eating sausages in skins Haarmann claimed were sheep's intestines. Another neighbour testified to the alarming number of youths whom he had seen entering Haarmann's Neue Straße apartment, but whom he seldom observed leaving the address. This neighbour assumed Haarmann was selling youths to the Foreign Legion;[37] another neighbour testified to having observed Haarmann throw a sack of bones into the Leine River. Two female acquaintances of Hans Grans also testified how, on one occasion in 1923, they discovered what they believed to be a human mouth boiling in a soup kettle in Haarmann's apartment;[64] these witnesses testified they had taken the item to Hanover police, who simply replied the piece of flesh may be a pig's snout.[n 9]

Haarmann (seated in front of chalkboard sketch of his apartment), during his trial in 1924

The trial lasted barely two weeks, and a total of 190 witness testified.[83] On 19 December 1924,[1] court reconvened to impose sentence upon both defendants. Judged sane and accountable for his actions, Haarmann was found guilty of 24 of the 27 murders and sentenced to death by beheading.[103] He was acquitted of three murders which he denied committing. Upon hearing the sentence, Haarmann stood before the court and proclaimed, "I accept the verdict fully and freely",[103] before adding: "I [shall] go to the decapitating block joyfully and happily."[94] Grans became hysterical upon hearing he had been found guilty of Incitement to murder and sentenced to death by beheading in relation to the murder of victim Adolf Hannappel,[104] with an additional sentence of 12 years' imprisonment imposed for being an accessory to murder in the case of victim Fritz Wittig.[105] Upon returning to his cell after hearing the verdict, Grans collapsed.[106]

In the case of Hannappel, several witnesses testified to having seen Grans, in the company of Haarmann, pointing towards the youth. Haarmann claimed this was one of two murders committed upon the insistence of Grans and for this reason, Grans was sentenced to death. In the case of Wittig, police found a handwritten note from Haarmann, dated the day of Wittig's disappearance and signed by both him and Grans, in which Grans agreed to pay Haarmann 20 gold marks for the youth's suit. As the note indicated Grans' possible knowledge in the disappearance of Wittig, he was convicted of being an accomplice to Haarmann in this murder and sentenced to 12 years' imprisonment.[107]

Haarmann made no appeal against the verdict;[105] claiming his death would atone for his crimes and stating that, were he at liberty, he would likely kill again.[110] Grans did lodge an appeal against his sentence, although his appeal was rejected on 6 February 1925.[111]

At 6 o'clock on the morning of 15 April 1925, Fritz Haarmann was beheaded by guillotine in the grounds of Hanover prison.[88] His executioner was Carl Gröpler. In accordance with German tradition, Haarmann was not informed of his execution date until the prior evening. Upon receipt of the news, he observed prayer with his pastor, before being granted his final wishes of an expensive cigar to smoke and Brazilian coffee to drink in his cell.[112][113]

No members of the press were permitted to witness the execution, and the event was seen by only a handful of witnesses.[112] According to published reports, although Haarmann was pale and nervous, he maintained a sense of bravado as he walked to the guillotine. The last words Haarmann spoke were: "I am guilty, gentlemen, but, hard though it may be, I want to die as a man."[114] Immediately prior to placing his head upon the execution apparatus, Haarmann added: "I repent, but I do not fear death."[115]

The true tally of Haarmann's victims will never be known. Following his arrest, Haarmann made several imprecise statements regarding both the actual number of his victims he killed, and when he began killing. Initially, Haarmann claimed to have killed "maybe 30, maybe 40" victims;[116][13] later, he would claim the true number of victims he had killed was between 50 and 70.[n 10]

Footnotes

A bronze memorial depicting the crimes of Fritz Haarmann. This memorial is on display at Hanover's Sprengel Museum

Haarmann was acquitted of three murders at his trial: those of Adolf Hennies, Hermann Wolf, and Hermann Bock. In each instance, strong circumstantial evidence existed attesting to his guilt.[130]

In the case of Hermann Wolf, police established that prior to the youth's disappearance, he had informed his father he had conversed with a detective at Hanover station. Haarmann is known to have given many of Wolf's clothes to his landlady in the days immediately following his 44th birthday (shortly after Wolf was reported missing).[124] Moreover, the youth's distinctive belt buckle was found at Haarmann's Rote Reihe address. Haarmann only chose to deny this murder midway through his trial, following heated threats made against him by the father of the murdered youth.[131]

Haarmann was acquitted of the murder of Adolf Hennies due to conflicting testimony regarding the circumstances as to whether he or Grans actually murdered the youth. Although Haarmann admitted at his trial to having dismembered Hennies's body, he claimed to have returned to his apartment and "found a dead body lying there," to which, he claimed, Grans simply replied, "One of yours." Grans would deny this claim, and would state that he had bought Hennies's distinctive coat from Haarmann for eight Marks, after having been warned the coat was stolen. Due to this conflicting testimony, and the lack of an actual witness to the murder, neither Haarmann nor Grans were convicted of Hennies's murder.[132]

In the case of Hermann Bock, several friends of his testified at Haarmann's trial that, prior to Haarmann's arrest, they were actively dissuaded from filing a missing person report upon the youth with police; these witnesses testified that Haarmann was insistent on filing the report himself (he had never done so). Other witnesses testified to having acquired various personal possessions belonging to the youth from Haarmann. In addition, a tailor testified at Haarmann's trial to having been asked by Haarmann to alter the suit. Haarmann repeatedly contradicted himself regarding his claims as to how he acquired the youth's possessions. It is likely that Haarmann chose to deny this murder due to evidence suggesting the murder had been premeditated, as opposed to being committed in the throes of passion. He had known the youth for several years prior to his murder, and Bock was known to be heterosexual. Due to his denial of having committed this particular murder, Haarmann was acquitted.[133]

Following Haarmann's execution, sections of his brain were removed for forensic analysis. An examination of slices of Haarmann's brain revealed traces of meningitis,[135] although no sections of Haarmann's brain were permanently preserved. Nonetheless, Haarmann's head was preserved in formaldehyde and remained in the possession of the Göttingen medical school from 1925 until 2014, when it was cremated.[136]

The communal grave of Haarmann's victims

The remains of Haarmann's victims which had been recovered were buried together in a communal grave in Stöckener Cemetery in February 1925. In April 1928, a large granite memorial in the form of a triptych, inscribed with the names and ages of the victims, was erected over the communal grave.[137]

The discovery of a letter from Haarmann declaring Hans Grans' innocence subsequently led to Grans receiving a second trial. This letter was dated 5 February 1925, and was addressed to the father of Grans.[138] In this letter, Haarmann claimed that although he had been frustrated at having been seen as little more than a "meal ticket" by Grans, Grans "had absolutely no idea that I killed". Furthermore, Haarmann claimed many of his accusations against Grans prior to his trial were obtained under extreme duress, and that he falsely accused Grans of instigating the murders of Hannappel and Witzel as a means of revenge. Haarmann claimed that his pastor would be informed as to the contents and the authenticity of the letter.[139]

Hans Grans was retried in January 1926. He was charged with aiding and abetting Haarmann in the murders of victims Adolf Hannappel and Fritz Wittig. Although Grans stated in one address to the judge at this second trial that he expected to be acquitted,[140] on 19 January, he was again found guilty of aiding and abetting Haarmann in both cases, although in this instance, he was sentenced to two concurrent 12-year sentences. After serving this 12-year sentence, Grans was extralegally interned in Sachsenhausen concentration camp. Following the conclusion of the Second World War, he continued to live in Hanover until his death in 1975.[141]

The murders committed by Haarmann stirred much discussion in Germany regarding methods used in police investigation, the treatment of mentally ill offenders, and the validity of the death penalty.[142] However, the most heated topic of discussion in relation to the murders committed by Haarmann were issues relating to the subject of homosexuality, which was then illegal and punishable by imprisonment in Germany. The discovery of the murders subsequently stirred a wave of homophobia throughout Germany, with one historian noting: "It split the [gay rights] movement irreparably, fed every prejudice against homosexuality, and provided new fodder for conservative adversaries of legal sex reform."[143]

Poster of Fritz Lang's 1931 film M

• Cawthorne, Nigel; Tibbels, Geoff (1993). Killers: The Ruthless Exponents of Murder. London: Boxtree Books. pp. 415–17. ISBN 0-7522-0850-0.
• Gibson, Dirk (2009). Serial Killing for Profit: Multiple Murder for Money. Santa Barbara: Praeger. ISBN 978-0-313-37890-4.
• Kavalovski, Joshua (2015). "The Haarmann Case: Remapping the Weimar Republic". German Quarterly, the. New Jersey: John Wiley & Sons, Inc. ISSN 0016-8831.
• Lane, Brian; Gregg, Wilfred (1995) [1992]. The Encyclopedia Of Serial Killers. New York City: Berkley Book. pp. 205–06. ISBN 978-0-425-15213-3.
• Lane, Brian (1995). Chronicle of 20th Century Murder. Wiltshire: Select Editions. p. 82. ISBN 978-0-425-14649-1.
• Lessing, Theodor (1993) [1925]. Monsters of Weimar: Haarmann, the Story of a Werewolf. London: Nemesis Books. pp. 11–156. ISBN 1-897743-10-6.
• Pozsár, Christine; Farin, Michael (2002) [1995]. Die Haarmann-Protokolle. Reinbek: Rowohlt Verlag. ISBN 3-936-29800-9.
• Tatar, Maria (1995). Lustmord. Sexual Murder in Weimar Germany. Princeton: Princeton University Press. ISBN 0-6910-1590-2.
• Wilson, Colin; Wilson, Damon (January 2007). The World's Most Evil Murderers: Real-Life Stories of Infamous Killers. Bath: Parragon Publishing. pp. 17–20. ISBN 978-1-405-48828-0.
• Wilson, Colin; Wilson, Damon; Wilson, Rowan (1993). World Famous Murders. London: Parragon. pp. 386–389. ISBN 978-0-752-50122-2.
• Wynn, Douglas (1996). On Trial for Murder. Pan Books. pp. 71–72. ISBN 0-09-472990-5.

Wikimedia Commons has media related to Fritz Haarmann.

• Fritz Haarmann at CrimeLibrary.com
• Contemporary newspaper account pertaining to Haarmann's trial and conviction
• Contemporary newspaper account detailing Haarmann's execution
• Fritz Haarmann's entry at executedtoday.com
• Image depicting Haarmann's severed head, preserved at Göttingen medical school until its 2014 cremation