Breaking traffic laws in Slovenia between 2012 and 2014

Analysis and visualization of two years' worth of traffic violations data.

obvestilo redarstva

According to data provided by state police, highway authority and local traffic wardens, there occurred a little less than a million traffic law violations between start of 2012 and September 2014. Given that there are 1,300,000 registered vehicles and 1,400,000 active driving licences in the country, this is a lot. A big majority of them are parking and toll tickets.

This article will try to answer these questions:

Overview of ticked issued and their distributions by town, days in week and months in year

Here are some charts with distributions of all issued tickets in Slovenia in interval between beginning of 2012 and end of 2014. Hour distribution is off - that's because the state police data didn't contain hours, only dates.

Not all traffic violations were created equal. Law enforcement officials pay more attention at infractions of certain types at specific locations, time intervals, days and months. The charts below would be very monotonous and dull, if one could not gather from them that:


Are traffic wardens just another type of tax collectors?

is the level of controlling parking fees constant, or does it rise over time? The charts below show the various aspects of parking tickets issued in several Slovenian towns.

There was a big hike in number of issued parking tickets in Ljubljana and Maribor the last three months of 2013. Whay could that be? One possibility is surely legitimate wish of county governments to instill some order in traffic regime, and get some revenue at the same time. The second possibility is that that those two cities are very much in debt, and that they try to earn money with more drastic parking rules.


Above: distributions of issued parking tickets on the territory of Ljubljana county between beginning of 2012 and end of 2014 by days in year, days in week and months in year.

The chief of LJubljana's traffic wardens says that they didn't increase the volume of issued traffic tickets. Rather, the county expanded the list of streets with payable parkings to many residential neighborhoods and tasked a public company to enforce the fees. This company hired a lot of new employees to do that, and they do collect revenue from that. But the point is that the county government issued the decree for financial reasons.

Ljubljana is the most indebted Slovenian county (204,705,050 Euros at the end of 2013, document), and they also have a very capable warden service. You can see the gradual expansion of ticketed zones in video below.

Video: gradual expansion of the ticketed territory in Ljubljana.

These streets in Ljubljana are the most risky in absolute terms for the drivers who don't pay the fee: Žabjak, Grudnovo nabrežje, Vodnikov trg, Puharjeva ulica, Štefanova ulica, Študentovska ulica, Pod klancem, Slovenska cesta and Stari trg.

And these are the most risky in relative terms - in density of tickets per kilometer - Študentovska ulica, then Kopitarjeva, Žabjak, Grudnovo nabrežje, Pod Klancem, Vrazov trg, Vodnikov trg, Za ograjami, Stari trg and Levstikov trg.


The town of Maribor is indebted, too, to the tune of 52.035.056 Euros at the end of 2013, and their traffic wardens are very active, too. Sorting streets of Maribor by number of parking tickets issued produces this list:

Video: gradual expansion of the ticketed territory in Maribor.

Other towns

Control group: there is some variation in number of tickets issued over time in Kranj, Celje, Novo Mesto and Nova Gorica, but it appears to be relatively constant in comparison to Ljubljana and Maribor.

Kranj Novo Mesto
Celje Nova Gorica


Answer: depends on the town. The hikes in Ljubljana and Maribor are so substantial, and county debts so high, that it's hard to believe in organic growth.

Most risky areas to park in bigger towns

These maps show number of parking tickets issued in different towns. Streets are colored according to this number, ranging from yellow to red. Red areas are the most risky.

Click images to enlarge.

Traffic wardens' activity during different times of day in LJubljana and Maribor

Some wardens apparently check the cars at different hours of day. While there are areas where it's not safe to ignore parking rules, there are also some areas where you can do that in some periods.

The maps show such areas in LJubljana and Maribor. How to read:

  • blue streets: most tickets were issued in the mornings,
  • yellow streets: most tickets were issued at midday, and
  • red streets: most tickets were issued in the afternoons or evenings

Traffic accidents, DUI and speeding

Are traffic policemen just another type of tax collectors?

There is a strong feeling that the police lay speed traps in locations having nothing to do with real danger. let's see if that's true.

Maps below show the situation in Ljubljana. Roads are colored proportionally to number of accidents that happened there in the last two years. Blue dots are where most speeding or DUI tickets were issued.

Temperature influence on traffic tickets issuing

Traffic violations that are more common as it gets warmer

There are two subtypes of infractions here:


Traffic violations that are less common as it gets warmer

Those that naturally decrease with falling temperatures, for example not using proper tires, animal transport, ...


Traffic violations with normal distribution

The most common violations, to which the seasons bear no effect, therefore they are distributed according to Gauss.


How the moon influences the drivers

Influence of the Moon is strong enough that emergency services in some cities prepare accordingly in days prior to full moon. Having close to one million traffic tickets in database, I wanted to chech, whether their number varies accordin to the mooon phases. I checked full moon and new moon dates.

The lunar cycle is 28 days long. To determine the influence of full moon, I counted violations on a full moon, and then on all the other days. Then I divided the second number by 27. If the numbers are approximately equal, there's no influence, but if they differ, this could indicate a lunar influence.

To display the numbers, hover the mouse pointer over the charts, which display the relationship in a graphical way.

There's no apparent influence on the state level. It's only apparent on a smaller territory. There are a number of possible reasons for that:

If we suspend disbelief in the fourth point for a moment and try to interpret the data, the rough picture is: full moon has a detrimental effect on safe driving, while new moon acts in a calming manner.

Highway toll - how the highway authority checks the drivers on highways for the sticker

The highway inspectors may not listen to your pleas if you get caught without a sticker, but they, too, have some habits, that a non-paying driver can exploit. Below is a map with locations where inspecitions have occurred in the last two years. They are nothing new in itself. Inspectors can be on any toll station, any highway ramp, and any petrol station or rest stop..

The chart below shows daily frequencies of tickets issued by day since the beginning of 2012.

Inspections are largely a seasonal matter. Most drivers are ticketed in the summer and around Christmas.

Hourly distribution shows that inspectors don't work at lunch time, or at least that their activity is hreatly diminished. That's one possible explanation. The other is, that there are less driver on the road during lunchtime, hence less tickets. The third explanation would be that the inspectors do ticket drivers at lunchtime, but they enter the events into evidence only after lunch.

So if you drive without a sticker, try to time the crossing of most probable inspection site between one and two in the afternoon, do it in the beginning of the week, and not in the summer.

Most frequent locations of DUI checks

This is not a discussion about dangers of drunk driving, but an attempt to deduce locations and time intervals with greatest threat to encounter a drunk driver.

In most town and city quadrants the story is the same: ticket frequency increases toward the end of the week, with an obvious peak on Saturday and Sunday. The police probably lay in wait for drivers returning from night on the town on Friday..

alkohol na Metelkovi

DUI ticketing around Metelkova PArty center in Ljubljana.

alkohol v Fužinah

DUI ticketing in Štepanjsko naselje and Fužine in Ljubljana.


Here's an interactive map with quadrants in which more than five DUI tickets were issued between 2012 and 2014.

Hover over a quadrant to see weekly and monthly distributions.

Data sources

All sources are not strictly open data, but they were obtained under law that regulates access to it. Most of the institutions complied immediatelly, but a few of them wanted to know the exact reason I needed it for.

According to this law, the state institution can refuse to hand out the data, if the preparation of it causes the staff unnecessary work. So I had to persuade them to put in that work, and they did it. Many thanks to all involved for that! For every traffic ticket issued, I needed location, date and type, which was the paragraph of the law that was broken.

Data sources:

About Android app

The app uses the same database as this analysis, but the display is adapted for mobile use. It's designed to check number of tickets of a specific type in the vicinity of user's location.

It's available in English and Slovenian, and limited to Slovenian territory.

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Start screen for ticket type selection

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Map display

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Summary with threat overview and various distributions

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List of addresses with number of tickets issued