The Crown Prosecution Service (CPS) has confirmed there is insufficient evidence to charges anyone over the death of Ryan Lamb.
The 20-year-old died of a single stab wound following a fracas in a takeaway in St Helens town centre.
Ryan, from Sutton, had been enjoying a Sunday afternoon out with pals when he was killed.
Three people were arrested in connection with his death but have never been charged.
The CPS has confirmed the trio - who are aged 17, 18 and 21 and from the Rainhill, Liverpool and Huyton areas respectively - will face no further action.
John Dilworth, Deputy Chief Crown Prosecutor of Mersey-Cheshire Crown Prosecution Service, said: “Merseyside Police brought a file of evidence to the Crown Prosecution Service (CPS) for charging advice following the death of Ryan Lamb in St Helens on April 23 2017.
“The evidence shows that a physical dispute had taken place between three men in an area not covered by CCTV. Each of them sustained injuries.
“At present there are no other witnesses. What happened after that cannot not be established by admissible evidence and is the subject of pure conjecture.
“At the present time, there is insufficient evidence to charge any of the suspects with a criminal offence.
“It is not the function of the CPS to decide whether a person is guilty of a criminal offence, but to make fair, independent and objective assessments about whether it is appropriate to present charges for the criminal court to consider.
“The CPS assessment of any case is not in any sense a finding of, or implication of, any guilt or criminal conduct.
“It is not a finding of fact, which can only be made by a court, but rather an assessment of what it might be possible to prove to a court, in accordance with the Code for Crown Prosecutors.
“CPS prosecutors must also keep every case under review, so that they take account of any change in circumstances that occurs as the case develops, including what becomes known of the defence case.
“If appropriate, the CPS may change the charges or stop a case.”