"Socio-economic status is a proxy for other things, but sometimes it's not. And we are trying to capture the group of people for whom it is the prime distinguishing characteristic in terms of school performance."
Doing so was crucial for society as a whole, he said, and reflected similar programmes in Australia, Britain and the United States.
"It is important in terms of the prospects of those individuals, and also important in terms of the country's capacity to tap their potential in the future."
During a recent meeting of the university council, members unanimously supported including poorer students and those with refugee backgrounds in its targeted admissions scheme.
It reserves a number of places in undergraduate programmes for students who have met the university entrance standard but not the guaranteed entry score for the programme of their choice.
Ten per cent of course places - possibly about 1000, Professor Morrow said - are reserved for targeted admission students, but that capacity is not met at the moment. If approval of the new group goes through, it could apply to students from 2015.
Figures on the socio-economic backgrounds of university students are not readily available.
However, a 2010 Ministry of Education study of a group of first-year students found those from low-decile schools were less likely to go on to study at bachelor's level, despite having the credentials to do so.
Professor Morrow said: "There is a widespread body of literature which shows that socio-economic status has an impact on school performance" which meant school results might not reflect potential.
Deciding which students would be eligible would be tricky but school decile was likely to be the most effective guide as it simplified the programme for students, minimised transaction costs and allowed the modelling of potential numbers.