Papua New Guinea's former attorney general Sir Arnold Amet says the country's judicial system is not well equipped to handle cases that might involve the death penalty.
The government is looking seriously at implementing capital punishment following a series of violent crimes against women and sorcery-related killings.
Sir Arnold was a criminal defence lawyer early in his career and became the Chief Justice.
He says criminal investigation practices, and legal processes aren't adequate.
"The competency of legal counsel, the legal profession and the judicial system leaves me with many issues of concern before we can progress through to deciding that the death penalty is the ultimate deterrent process."
Sir Arnold Amet says his other concern is that all trials in PNG are presided over by a sole judge, not a jury.
The government plans to introduce the death penalty for a range of violent crimes.