Australian news outlets and politicians have repeatedly claimed the country is in the grip of the worst youth crime wave in history.

These claims are contradicted by official data sources that show youth crime has plummeted in every state and territory in Australia to near record lows.

University of Queensland mathematician Matthew Sutton said statistics could easily be misused to draw false conclusions.

He said even when the statistics quoted were technically true, they could be skewed to create incorrect and misleading conclusions. 

"It's a very natural tendency to want to tell a story with the numbers, but it's only going to work if people are fair and unbiased in their use," Dr Sutton said.

ABC Brisbane asked statisticians and criminologists to explain the common ways in which data can be used or skewed to misrepresent youth crime data.

Zooming in on short-term trends

The Courier Mail has claimed that Queensland's youth crime rates have skyrocketed to crisis levels.

In one article, it cites Australian Bureau of Statistics data that shows in 2022-23 Queensland's youth offender rate per 100,000 increased from 1,863 to 1,925 in 12 months.

When we plot this increase on a graph with additional ABS data extending back to 2008-09, it looks like this:

Dr Sutton said it was unwise to zoom in on short-term data while ignoring the long-term trends.

He said short-term data tended to have a high level of "noise" or fluctuation, making it an unreliable indicator of overall trends.

Using a bad baseline

During the COVID-19 pandemic, crime rates plummeted in Australia, gradually rising in the following years as lockdowns eased.

Even when the offences were still lower than pre-pandemic levels, news outlets were reporting that crime rates were skyrocketing year-on-year.

Most official data sources provided a caveat that any year-on-year increases post-lockdown should be interpreted with caution, given the unusual baseline. 

9News reported "shocking figures" that Alice Springs saw a 59 per cent increase in property offences in 2022, but provided no caveats about COVID lockdowns. 

An ABC News article claimed that between September 2021 and September 2022, crime rates in the NSW town of Dubbo increased in most categories. 

However, the ABC failed to provide the caveat that the increase came off the back of historic lows for the region post-lockdown. 

Dr Sutton said statisticians had to be careful when choosing a baseline to compare two points in time, since a bad frame of reference could produce misleading results.

Obfuscating number and rate

In January, the Sunshine Coast News reported the region was experiencing the worst crime wave in its history.

As evidence, it cited Queensland Police Service data indicating the number of offences committed in 2023 was the highest since records began in 2001.

However, even though the total number of crimes had increased, the actual crime rate had been nearly cut in half during that period.

In criminology, the crime rate is the number of offences relative to the size of the population.

University of Queensland associate professor Renee Zahnow said criminologists relied on crime rates, as offence numbers alone were a misleading measure of crime.

"When we have a population boom we have to account for that."

She said crime rates were the best way to compare crime between time periods and geographical areas, since they controlled for population when numbers did not.

In the lead-up to Saturday's state election, LNP leader David Crisafulli has cited victim numbers as evidence of a worsening crime epidemic sweeping Queensland.

Mr Crisafulli did not respond to ABC questions around why he uses victim numbers instead of victimisation rates or youth crime rates.

Victimisation rates compare the number of people who directly fall victim to crimes relative to the population. 

Those crimes include assault, threat of assault, sexual assault, and other offences directly against a person. 

Australian Bureau of Statistics data shows that victimisation rates have fallen across the board, including Queensland.

In a television segment, 9News confused rates with numbers, incorrectly claiming that Queensland's crime rates were the highest in a century.

All of the Queensland Police Service data they cited referred to numbers and not to rates as claimed in the segment.

Cherry picking small sample sizes

Dr Sutton said it was a bad idea to use small sample sizes when trying to see long-term trends in data.

He said a smaller sample size created larger noise and spikier graphs, causing extreme variation from year to year that did not reflect overall trends.

In 2022, the Courier Mail reported that in the rural town of Mundubbera the number of crimes skyrocketed to 19 in October, up from three in June, a staggering 533 per cent increase.

That pales in comparison to October 2021, when a single drug bust caused Mundubbera's crime rate to increase 1,375 per cent in one month. 

Small sample sizes also come into play when news outlets cherrypick subcategories within subcategories of crime to claim there is an upwards trend.

The Herald Sun reported that aggravated burglary offences for those aged 10-14 within Victoria between 2022 and 2021 increased from 91 to 164.

The data was cited from the Crime Statistics Agency, however the full dataset shows Victoria's broader youth crime rates have fallen significantly alongside every other state.

Comparative Australian Bureau of Statistics data shows Victoria has the third-lowest youth crime rate in the country.

While most categories of crime have fallen across Australia, notable exceptions include rape, domestic violence and sexual assault. 

In Queensland the rate of physical assaults has also skyrocketed since 2016. 

However Professor Zahnow said the increased reports of domestic violence and sexual assault were likely caused by increased awareness, reporting and enforcement. 

She said the increase in Queensland's assaults were driven in part to the way it was reclassified in 2016 to include assaults in a domestic context. 

Why does this happen?

University of Southern Queensland communications professor Andrew Hickey said news outlets had made claims of youth crime crises for many years.

He said analysis of newspapers over time showed older generations had always claimed that the younger generations were morally deficient and criminally inclined.

Professor Hickey said young people often served the role of the "folk devil", the cultural scapegoat who took the blame for society's problems.

He said the folk devil was usually young people, immigrants or other marginalised groups who did not have the power to vote or write newspaper opinion pieces.

"Folks who are marginalised don't have a voice, they don't have the capacity to write back and square the ledger," Professor Hickey said.

"Young people don't have access to prosecute their story, their narrative, their place in the world like older folks do.

"If we can point to a group and say, 'There's the problem', that affirms our own positionality and makes us feel a little more comfortable about the world we live in."

The ABC has sought comment from The Courier Mail, 9News, Sky News, Townsville Bulletin, Herald Sun, Sunshine Coast News and the LNP.