Breaking traffic laws in Slovenia between 2012 and 2014
Analysis and visualization of two years' worth of traffic violations data.

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:
- Are traffic wardens and traffic police just another type of tax collectors for the state and counties?
- Do traffic wardens really issue more tickets now than in the past, or is that just my perception?
- Which zones in bigger towns are especially risky, should you forget to pay the parking?
- Are traffic wardens more active in specific time intervals?
- Does the police lay speed traps in locations with most traffic accidents? What about DUI checking?
- How does temperature influence the number of issued traffic tickets?
- Does the moon influence the number of issued traffic tickets? If so, which types?
- Where and when are drivers most at risk of encountering other drunk drivers?
- Where does the highway authority check for toll, and when to hit the road if one does not wat to pay it?
- How can we drive safer using open data?
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:
- if you have to drive drunk, don't do it on weekends, and especially not on Saturdays. The police does not joke around at that time. Most drivers get DUI citation in the summer, and not so much in December, which is a big festivity month.
- the likelihood of getting a speeding ticket is the same through the week, except in Ljubljana and Kranj. In addition to police, traffic wardens are checking for speeding, too - but not so much at the weekends.
- if you refuse to pay for parking, you can leave your car without worry at weekends anywhere, except at the coast.
- the bigger the town, the more the accidents at the weekend. That's probably related to DUI. Also, most accidents happen in the summer months.
- the police is not so active on weekends. Maybe because there are less cars on the roads then.
- local traffic wardens and the police check parking in a very seasonal way. Mostly in the beginning of the year, except in the capital.
Parking
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.
Ljubljana
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.
Maribor
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:
- Partizanska cesta
- Ulica Moše Pijada
- Partizanska cesta
- Ulica Veljka Vlahoviča
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.




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.

Dots: DUI tickets
The police check for intoxications mostly on main streets with most accidents. Most DUI ticket locations correspond with accident locations. This is either because the police knows, where these locations are, and patrol there, or they automatically check crashed drivers for inebriation.
These locations are pretty scattered, leaving one to conclude that most DUI tickets are issued by patrols in cars, who follow erratically driving people.

Dots: speeding tickets
900 tickets issued on Parmova, a not very busy street with a low speed limit. No accidents were reported here in last two years.
Next in line are Verovškova street with 700 tickets, and Dunajska street with 500 tickets.

Dots: speeding tickets
Police and traffic wardens use different methods for speed limit checking and DUI checking.
In this case, the modus operandi seems to be speed trapping with laser meters, so the locatioons are fewer, but with more tickets issued on each one. Pay attention to discrepance between streets with most accidents and streets with most speeding tickets issued.

Dots: speeding tickets
The discrepance that stands out the most in on Streliška street in LJubljanan. Speed limit there is 30 km/h, and there were 1800 tickets issued there in the last two years.
The traffic wardens' chief says that there are days when they stop a speeding driver every five minutes threre. It's their favorite location, and one that they won't give up.
Following; Dolenjska street at number 11 with 500 tickets issued, and Trnovski pristan at number 10 with 400 tickets issued.
Temperature influence on traffic tickets issuing
Traffic violations that are more common as it gets warmer
There are two subtypes of infractions here:
- seasonal - because there are simply more vehicles on the road during the summer, for example highway toll (many foreign tourists forget to buy the sticker) and maybe driving school. Also, many motorcycle drivers forgert to don the helmet.
- those that genuinely get worse because of frayed nerves in hot cars: overtaking, ignoring yield, speeding, ...
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:
- the first and the most probable is, that there are fewer infractions on a smaller territory, so the statistics are subject to swaying. There simply aren't enough material to make a credible claim for a lunar influence. If we proceed by putting this aside, we could tentatively conclude, that
- maybe some police bosses in specific towns are aware of the lunar influence, so they prepare accordingly. That could be the explanation for the differences betweeen various towns, as seen on the charts below.
- maybe the lunar influence is more obvious in towns and cities, because people live in close proximity to each other
- maybe the moon really influences the number of issued traffic tickets.
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..

DUI ticketing around Metelkova PArty center in Ljubljana.

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:
- traffic wardens of Ljubljana
- state police
- DARS
- Ljubljanska parkirišča
- traffic wardens of Maribor
- traffic wardens of Kranj
- traffic wardens of Celje
- traffic wardens of Novo Mesto
- traffic wardens of Nova Gorica
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.

Start screen for ticket type selection

Map display

Summary with threat overview and various distributions

List of addresses with number of tickets issued