It happened in the late '70s in USSR. - “Watch out!” almost shouted the driver as he saw detective Kronin to jump from a long-distance bus on the icy asphalt. - “I am here!!!” 
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Salt and Ice

Salt and Ice

It happened in the late '70s in USSR.

“Watch out!” - almost shouted the driver as he saw detective Kronin to jump from a long-distance bus on the icy asphalt. - “I am here!!!” 

The driver's joy seemed to have no limit. “I thought you'd never come!” - he greeted the detective. “The snow hasn’t been cleared since the morning, and the radio warned of a blizzard and black ice!”

“Never mind,” muttered detective Kronin. “You’d better tell me the facts as they actually happened; and, please, speak up! I can hardly hear anything with those engines roaring and fans crying their fight songs!” 

The road accident occurred near the stadium, which at that time held a track race of the “heavy duty” Moskvich-412R cars. - “So, is this the place where your car was damaged?” Kronin mused.

“Yes,” agreed the driver. “I stopped at the curb and dozed off. At some point, I felt a heavy impact on the side. I opened my eyes, but, alas! too late to see the offender.

The only thing I remember is the squealing sound of his tires. Look, here is the tread!” the driver pointed at a black line near his car.

Detective lowered his knee onto the pavement, took off his fur mitten and rubbed his finger against the remaining tire trace. With that, he put the finger to his lips and tasted it. Seeing the puzzled look in the driver's eyes, he hastened to forestall his questions.

“Nothing to worry about, dear driver, I know where to find the offender. In the meantime, I'll contact the traffic police post via radio, and give them the information they need to apprehend the criminal.”

Question:

Why is detective Kronin sure that he will easily find the culprit?