A fight involving dozens of young Sudanese-Australian people in Melbourne has led to renewed debate about crime and policing.

The South Sudanese Community Association says the incident was "immature young people" rather than anything gang-related.

But Home Affairs Minister Peter Dutton says the Victorian Government needs to take action.

"[Victorian Premier Daniel Andrews] needs to, I think, come out and start sorting this out because at the moment people are getting hurt and somebody's going to be killed."

Since the issue hit the headlines in January, new data has been released, providing an insight into crime rates between April 2017 and March 2018.

Here's what it shows us, in four charts.

What are the nationalities of offenders?

Victoria Police supplies the Crime Statistics Agency with information on the number of individuals alleged to have committed a crime, their age and the country where they were born.

It's important to remember any individual is only recorded in this dataset once, even if they have committed multiple offences. And this encapsulates all types of crime, from relatively minor incidents where only a caution was given, right through to the most serious offences.

There were just over 80,000 unique offenders in 2017-18 and not surprisingly, the majority, around 59,000, were born in Australia.

That means almost three-quarters of all offenders were born in Australia, compared to 1 per cent who were born in Sudan.

The chart above shows the proportion of offenders for the 20 nationalities with the highest number of offenders in 2017-18.

To show how these rates compare with the number of people of each nationality in the Victorian population, we have included 2016 census data for those aged 10 or older.

It's worth noting that in both datasets, the Sudan category includes people born in both Sudan and South Sudan.

Are Sudanese people over-represented in the crime statistics?

If all nationalities were equally represented in the crime data, the proportion of offenders for each country would match their proportion in the overall population.

In fact, the proportion of offenders born in 10 different countries was higher than their representation in the population overall.

Of the 80,000 Victorian offenders, 879 were Sudanese.

But the proportion of Sudanese offenders was six times higher than might be expected for the number of Sudanese-born people living in Victoria, which was around 8,000 in 2016.

Does age make a difference?

The discussion on Sudanese crime in Victoria has focused in particular on young offenders.

The Sudanese community is younger than the overall population: 33 per cent are aged 10-25, compared with 21 per cent of the overall Victorian population.

That skew is reflected in the age group split of offenders.

Sudanese-born offenders aged between 10 and 25 are over-represented in the offender group, compared to their overall population.

Notably, the same is true for those born in Australia and New Zealand, as well as across the entire offender group.

Which offences are committed by different nationalities?

Sudanese-born people were in the top three nationalities for several offences, including aggravated burglary and serious assault.

In this case, the data represents the number of alleged offender incidents, so people can be counted multiple times. That means it would be misleading to compare it to the proportion of each nationality in the Victorian population.

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