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The Crime Severity Index explained

Every year, the findings of a familiar national statistical survey make the news during the last week of July.


Every year, the findings of a familiar national statistical survey make the news during the last week of July.

It is Statistics Canada's annual report of "Police Reported Crime Statistics" for the previous year, a report that provides numbers and values for communities across Canada on police-reported crime.

That report includes numbers for the Crime Severity Index, as well as the Violent Crime Severity Index and Non-Violent Crime Severity Index.

The release of those numbers is followed closely by residents in North Battleford, who complain annually over the city topping the Crime Severity Index for communities over 10,000 on a per capita basis for the years 2009 to 2012.

The reality is, however, many people still don't exactly know what goes into putting together a Crime Severity Index, or exactly what the numbers really mean for the community.

To help us understand what it is, the News-Optimist has received some information from the RCMP detachment about the Crime Severity Index and what it means. Among the background information provided to us from RCMP Insp. John Sutherland was the report Measuring Crime in Canada: Introducing the Crime Severity Index and Improvements to the Uniform Crime Reporting Survey authored by Marnie Wallace, John Turner, Colin Babyak and Anthony Matarazzo, on which much of the information in this story is based. Also provided was additional information, including information on the Uniform Crime Reporting Survey upon which the CSI is based.

One question on the minds of people is: what is the Crime Severity Index, and how is it different from the traditional "Crime Rate?"

According to Statistics Canada, the traditional "crime rate" measures the volume of crime coming to the attention of police. The crime rate is simply a count of all criminal incidents reported to and by police, divided by the population.

In determining the crime rate, the seriousness or "severity" of the crime incidents are not taken into account. Under that measure a first-degree murder counts the same as mischief, or a theft under $5,000.

That posed some difficulties because, according to Statistics Canada, the traditional crime rate is heavily influenced by fluctuations in high-volume, less-serious offences such as mischief and thefts under $5,000. Meanwhile, the impact of the most serious crimes, such as murder, was almost nil on the crime rate.

As a result, and on the request of the police community who recognized the limitations of the crime rate, in 2009 Stats Canada introduced a "new, additional tool" to track changes in the severity of police-reported crime - the Crime Severity Index.

According to Statistics Canada, the CSI measures the change in volume of particular crimes, while also taking into account the relative seriousness of the crime.

The index is calculated with each type of offence assigned a seriousness "weight." That weight is a number derived from actual sentences handed down by courts in all provinces or territories. The weights are calculated using the five most recent years of available sentencing data.

Statistics Canada's 2009 report lists examples of the "weights" given to various offences. At the time, first-or-second degree murder was assigned a weight of 7,042. Manslaughter is weighted at 1822, attempted murder at 1411 and level 3 sexual assaults at 1,047.

The weighting goes on down the line, from discharging a firearm with intent, to level 2 sexual assault, to robbery, to level three assault, and on down the list.

At the low end of the scale was theft under $5,000 assigned a weight of 37, mischief at 30, level 1 assault at 23, failure to appear at 16, disturbing the peace at 9 and at the lowest end, possession of cannabis at 7.

The "weights" are adjusted every five years, and new values came into effect starting with the 2011 statistics to reflect recent sentencing practices and account for new Criminal Code offences. The changes meant breaking and entering and fraud would contribute more to the overall Crime Severity Index than previously, while robbery, mischief and theft under $5,000 would contribute less.

The end result is that serious offences now have more of an impact on the Crime Severity Index than they would to the old traditional crime rate. Using examples from Statistics Canada's 2009 report, breaking and entering made up 10.2 per cent of the total across Canada under the old crime rate. But with the greater weighting under the Crime Severity, those same offences made up 24.9 percent.

Robbery, too, counts for more under the CSI than under the crime rate, at 11.2 percent compared to 1.5 percent.

But thefts under $5,000, which made up 25.6 percent of the traditional crime rate, and mischiefs, which made up 16.6 percent of the total crime rate, made up less of the total under the CSI, to 12.4 percent and 6.4 percent respectively.

Perhaps the biggest misnomer is calling this measure the "Crime Severity Index." That gives people the impression that the data focuses entirely on the most severe crimes, when all it really refers is to the fact that serious offences are given higher weight in the calculations. Maybe a better name for it should be the "Weighted Crime Index" or something similar, but Crime Severity Index is what it is known as.

The more violent offences are actually measured by Statistics Canada in a separate survey called the "Violent Crime Severity Index." There, the more serious and violent Criminal Code offences are given various weights and calculated on that basis. Those include robbery, assault, assault with a weapon or causing bodily harm, aggravated assault, sexual assault, and murder, attempted murder and manslaughter, among others.

There is also a Non-Violent Crime Severity Index covering the non-violent offences including mischief, breaking and entering, cocaine trafficking, theft under $5,000, fraud, and so on.

How are numbers tabulated for the CSI?

According to Statistics Canada, it is calculated by counting the number of police-reported incidents, then multiplying it by the assigned weight for that offence.

All weighted offences are then added together and divided by the corresponding population total.

To make the index easier to interpret, it is standardized to equal 100 for the base year of the survey, which is 2006, using a system similar to the Consumer Price Index.

The data used for the index is compiled from a couple of major sources. The first is the Uniform Crime Reporting Survey, which produces a record of crime and traffic statistics since 1962. There are two levels - an aggregate survey as well as a more detailed incident-based survey called the UCR2.

That survey collects information only on crimes that come to the attention of police and are substantiated by them. It does not count every crime that happens in Canada, as some are never detected or never get reported to the police.

The other data comes from the Adult Criminal Court Survey, a measure that provides statistical information on the processing of cases through the adult criminal court system.

There are some challenges, according to Statistics Canada, because it is difficult to factor in such things as time served on remand, repeat offenders, conditional sentences and life sentences, due mainly to a lack of data.

This means the CSI is also somewhat of an imperfect measure of the crime going on in a community. Still, it does provide some comparisons as to whether police-reported crime is getting better or worse over time, as well as providing useful comparisons to other communities.

Here are other common questions and answers related to the high CSI numbers seen in North Battleford in recent years.

One: North Battleford has been number one in cities over 10,000. Are there other groupings for larger cities?

Answer: There is a grouping of "census metropolitan areas" over 100,000. For 2013, the CMA with the highest CSI in Canada was Regina, with a CSI of 109. Saskatoon is second at 99.1.

However, since 2009, North Battleford's CSI score has ranked the highest among all crime-reporting communities over 10,000 population, including all the ones over 100,000 - leading some local people to voice concern about the city being perceived as the "Crime Capital of Canada".

CSIs are also measured for provinces and territories. In 2013, Saskatchewan's CSI was 125.7, the highest among all the provinces but behind all three of the Territories. What is most apparent from a quick look at the numbers is that the CSI tends to be higher as the population base measured becomes more sparse. The more dense the population base, the lower the score, in general.

What is not released are CSI numbers for communities under 10,000 population. Those would be interesting to see.

Two: What crimes or statistics used to create the CSI are influencing our high number?

Answer: As it turns out, a lot of the ordinary crimes that people have to deal with make up a very high amount of the CSI. According to StatsCan the top contributors to the national CSI are crimes as breaking and entering, theft $5,000 or under, robbery, fraud, theft of a motor vehicle and mischief.

While serious offences such as murder are given the most weight, in actuality they make up a very small total of the CSI.

The top contributors to the national CSI also are well known as big problem areas in North Battleford. According to Insp. Sutherland of the RCMP, offences contributing to North Battleford's overall CSI include: mischief, breaking and entering, cocaine trafficking, robbery and theft.

"The categories of mischief and breaking and entering accounted for almost half of the non-violent CSI and over 30 per cent of the overall CSI," Sutherland stated in a release. "Mischief includes offences ranging from an unwanted person at a residence to vandalism."

"As for the category of Violent CSI, the top offence in the violent CSI is robbery, which contributed to 20 per cent of the violent CSI. Of the top five offence types contributing to the overall CSI, robbery is the only violent offence and accounted for 5 per cent of the overall CSI.

"Another factor impacting the non-violent CSI is disturbing the peace. This is due to the frequency of this type of complaint. In 2013 North Battleford members responded to more than 1,000 disturbing the peace complaints, which is a 6 per cent reduction from 2012. Also significant is the 17 per cent reduction in the numbers of assault with weapon and/or assault causing bodily harm."

Three: A high amount of intoxicated individuals are picked up by police and those are scored as Criminal Code mischief. How do these and other non-violent offences affect our overall CSI score?

Answer: The best answer is to say "it all adds up." Adding the cases of intoxicated individuals to the other mischief that goes on in the community, such as vandalism, graffiti and so on, contributes to the number of mischiefs for North Battleford that go into the final calculations. And, of course, because these crimes are non-violent, mischief makes up an even greater portion of the "non-violent CSI" index.

Mischief would be assigned a "weight" under the CSI measure, and that is multiplied by the total number of incidents of mischief in the community. The final "weighted total" is added to all the other "weighted totals" for all other offences. Once added together, the final result is then divided by population and indexed to 100, and that results in the final CSI score for the community.

So in the end, the number of mischiefs do make a significant contribution to the CSI.

However, it does not have the same impact on the CSI as it does on the crime rate, where mischiefs have exactly the same weight as the more serious offences. Under the CSI calculation, mischiefs are weighted near the bottom of the scale, and have less of an impact on the final CSI than they would the traditional crime rate.

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