The 30-year-old murder near the fictional home of Sherlock Holmes has been solved after the killer was snared with a bloody footprint.
Sandip Patel, who ran errands for his father’s newsagent Sherlock Holmes News on Baker Street in London, stabbed Marina Koppel more than 140 times in her rented flat in nearby Chiltern Street on August 8 1994.
The 21-year-old student’s finger marks were found on a carrier bag in Mrs Koppel’s kitchen but he was not treated as a suspect at the time.
He was charged with her murder last year after his DNA was matched to hair on the victim’s ring and he was linked by a bloody footprint on a skirting board.
During the attack, he had extracted Mrs Koppel’s bank card pin and used the number to withdraw money near his home, it was alleged.
Patel, now 51, had denied murder but declined to give evidence in his defence.
The Old Bailey jury deliberated for three hours and 10 minutes to find him guilty.
Jurors had heard how Colombian-born Mrs Koppel had met her husband David while working as a hotel chambermaid.
She later worked as a masseuse and offered sexual services to around 100 “well-to-do” men “if the price was right”, jurors were told.
According to her late husband, her clients had included successful people, businessmen, a doctor, and even a politician.
Mr Koppel, who lived in Northampton, did not approve of her work but “accepted it”, jurors were told.
It caused tensions in the relationship and the couple had argued on July 31 1994, prompting Mr Koppel to travelled home alone.
Prosecutor William Emlyn Jones KC said little was known of Mrs Koppel’s last movements.
On the evening of August 7 1994, she had entered a poker tournament at the Victoria Sporting Club casino and met a client at a Heathrow hotel and before returning to London.
The mother-of-two’s last known sighting was a visit to Midland Bank on Baker Street at 1.42pm the following day.
All these years later, they have been identified – they are the defendant’s prints – they were made by the sole of his left foot
That evening, Mr Koppel returned to her flat near Baker Street Tube station to find she had been murdered.
She was covered in blood and wearing only black lacy lace-up lingerie that she might wear if she was expecting one of her clients, jurors were told.
Mr Emlyn Jones said she had been stabbed more than 140 times during the “sustained and savage” attack.
He told jurors: “Marina Koppel was brutally murdered. It has taken a terribly long time to solve it, but we now have evidence that she had this defendant’s hair stuck to the ring she was wearing when she was attacked and killed; and his bare foot was pressed against the skirting board next to her.
“And that, the prosecution say, can only be because it was him who killed her all those years ago.”
Even though Patel’s finger marks were found on an unbranded plastic bag in the kitchen, he was not treated as a suspect because he would have handled bags from nearby Sherlock Holmes News, because it was run by his father at the time.
Patel only became a confirmed suspect in 2022 after his DNA was matched to a hair found by a scientist on the ring in 2008.
Although technology was still not advanced enough then for scientists to get a DNA profile, it was preserved until 2022 and re-examined.
The bloody footprint was found at the scene in 1994 and matched to Patel after he was made a suspect, the prosecutor said.
Today’s result provides an example where forensic science, newer technologies and collaborative working practices have had a positive impact in bringing a brutal killer to justice
Mr Emlyn Jones told jurors: “You may have little trouble concluding that if those footprints were made in Marina’s wet blood, then that can only be because they were left by her killer – someone who was in that room, barefoot, at the time of her blood being on the skirting board.
“All these years later, they have been identified – they are the defendant’s prints – they were made by the sole of his left foot.”
Following his arrest, Patel denied knowing the victim but said he would run errands for his father.
He told police: “I continue to have no recollection of Marina Koppel, her address, or this incident. I have no idea how my fingerprint came to be on this carrier bag or how a hair of mine was present.”
He was rearrested in 2023 after his footprint was identified and answered “no comment” to questions.
Mr Koppel died in 2005, never discovering who murdered his wife.
Dan Chester, the Met’s forensic lead for cold case homicide investigations, said: “Unsolved historic murders can be among some of the most complex and challenging cases for police to solve.
“However, today’s result provides an example where forensic science, newer technologies and collaborative working practices have had a positive impact in bringing a brutal killer to justice.
“This was a great team effort with the forensic scientists, fingerprint experts, the forensic manager and the investigating team all playing their part in solving Marina’s murder.
Members of the victim’s family, Mary and Martin Koppel, said: “Marina Koppel, our sister-in-law, was an extremely bright, highly intelligent and charismatic person, who saw good in her family and all people she met.
“She wanted to give them everything they needed, especially her two children and nephew who grew up in Colombia.
“Her family and friends would have been in a much better place because of her abundance of energy for life had she not died.
“Marina was a daughter, a sister, a mother, a loving aunt, a daughter-in-law and a sister-in-law who was much loved by all of us as she loved all of us.
“Had Marina lived, all of the lives of her family and friends would have been enriched and further evolved.
“We have all suffered these many, many years because we lost Marina so early in life”.
Detective Superintendent Katherine Goodwin said: “We are so pleased that finally Marina’s killer has been brought to justice. It is extremely sad that her husband did not live to see this day.
“Our thoughts and sympathies are with Marina’s family and friends and we hope that today’s verdict will bring some closure for them.
“Even though Patel has been convicted for the brutal murder of Marina, we may never know the reasons for his actions on that day.
“Unsolved murder cases are never closed and it is due to the developments of forensic techniques we have been able to identify the suspect for this barbaric crime.”
Sir Arthur Conan Doyle’s fictional detective Sherlock Holmes lived at 221B Baker Street.
Patel, of Finchley Road, north London, looked up at the public gallery as the verdict was delivered.
He was remanded into custody to be sentenced at the Old Bailey on Friday.
