Fingerprinting

A large-scale fingerprinting operation began in 2002. All males aged between 15 and 45 from Höchst and Unterliederbach, as well as male commuters in that age bracket who used Frankfurt-Höchst railway station (Frankfurt's second busiest) at the time of the murder, were invited to submit fingerprints samples voluntarily. By 2014, 98.65% of 15-to-45-year-old males from Höchst and 92.95% of those from Unterliederbach had done so.^[6]

False leads

Among other false leads, an American woman told the police that her German ex-husband was the murderer. However, she later recanted her accusation, admitting that she had made up the story to take revenge on her ex-husband after an acrimonious divorce.

Manfred Seel

On 19 May 2016, the Hessen State Office of Criminal Investigations (Hessisches Landeskriminalamt) in Wiesbaden announced that Manfred Seel was being looked into as a suspect.^[7] Seel died in 2014 aged 67. He lived a seemingly ordinary life, holding the same job for decades, raising a family, having no criminal record and being an active and respected member of his local community, among other things being in a jazz band. However, after his death, his daughter was looking through his belongings in a rented storage facility and found human remains and diaries containing graphic descriptions and sketches of murders. The police are certain that Seel murdered at least five women, and perhaps as many as nine – primarily sex workers, drug addicts and people suffering from mental illnesses – between 1971 and 2004.

Seel was considered a potential suspect primarily because he and Brübach lived in the same area, rather than there being any evidence linking him to Brübach's murder. Brübach does not fit Seel's victim profile in terms of age and gender. However, Seel did exhibit sexual sadism in his presumed murders and kept the genitals of some of his victims. In October 2017, the press officer of the Frankfurt Police announced that Seel had been excluded as a suspect in Brübach's murder.^[8]

Unidentified ponytailed man

The prime suspect is a male aged between 20 and 30 with either a cleft lip or a large scar on his upper lip and of a generally unkempt appearance. This man was seen by several people, all of whom contributed to drawing up the composite sketch. The sketch was shared with law enforcement authorities worldwide, but no suspects matching the image have emerged. The first person to see the suspect on the day of the murder was a 12-year-old girl walking through the Liederbach Tunnel, where Brübach would later be murdered. The girl reported that she saw the man coming out from behind a bush. He was wearing a hat, with a ponytail visibly dangling from the back of it. About a week later, a man turned up at the offices of a law firm and told a lawyer, "I've only just been released from prison and I've already screwed up." The lawyer directed the man to another law firm, which dealt with criminal law matters, but the man never went there. A week after this sighting, another witness – who gave Brübach private academic tuition – came forward. She stated that a few days before Brübach's murder, she had seen him in the company of a man who closely resembled the composite sketch. She was sure that she had seen this man more than once in the recent past. The woman believed to have been the last person to see Brübach alive, at Bruno-Asch-Anlage, provided a description that differed from that of the ponytailed man. According to this witness, she was sitting on a park bench when Brübach, who was alone, sat down on the same bench and smoked a cigarette. The witness briefly engaged in small talk with Brübach before leaving the bench. After she had left, she turned around and saw two men sit down on the bench – one to Brübach's left and one to his right. Brübach was murdered between 10 and 25 minutes later, 500 metres away in the Liederbach Tunnel.

Unknown caller

On 7 April 1998, the day after Brübach's funeral, a man called the police to report that he was the murderer. He reported that he was at Höchst railway station and would wait there for the police to come and arrest him. When the police arrived, he was nowhere to be found. Parts of the call were made public and can be heard on YouTube. The caller has never been identified.

Grave

In October 1999, an unknown person entered Höchst Cemetery at night and dug 1.2 metres into the ground, down to Brübach's coffin. The coffin was not opened. The police believe that the act was committed by a mentally disturbed person with no connection to Brübach or his murder. Under German law, graves in public cemeteries are maintained by the state for a certain period of time (20 years in Hessen, the state where Brübach lived), after which the deceased person's family must pay to lease the grave site if they wish to keep their loved one there. If the family does not pay, the headstone is removed and the grave is reused for a new deceased person. Brübach's father died aged 59 in 2015 and no other relatives could afford to pay the fees to keep Brübach's grave in place, so a public initiative was launched to fund a memorial stone. In March 2018, after Brübach's grave was reused, a memorial stone was erected under a nearby tree, within sight of the grave.

Rewards offered

The Frankfurt am Main Prosecutor's Office is offering 15,000 euros for any information leading to conviction of Brübach's murderer. A private individual has added 5,000 euros to this, making the total reward sum 20,000 euros. Another private individual offered a time-limited 80,000-euro reward, but it expired in May 2016 with no one coming forward. The 20,000-euro reward remains in place.