Latvia is a relatively small but diverse country. According to the CIA’s World Factbook the 2,231,503 population is 57.7% Latvian, 29.6% Russian, 4.1% Belorussian, 2.7% Ukrainian, 2.5% Polish, 1.4% Lithuanian, and 2% other.
In spite of economic difficulties people are still driving cars in Latvia, and just like in many countries drivers often express themselves by decorating their vehicles (think  Obama and Palin bumper stickers in the U.S.). I personally think there are better ways to show ones affinity or dislike towards something, but my personal views are besides the point here.
In early February, latvietislatvija.com, a web site hosted in the U.S.  published the personal identity codes, license plate numbers, addresses and names of “disloyal” Latvians, i.e.,  drivers who affix Russian symbols to their cars. An ongoing investigation should soon reveal how the drivers’ identities were compromised.
More at Delfi in Latvian and Russian.