Finnish tradition is to assess fines according to gross income. For years, this was based on the honor system. Finnish police would ask the person pulled over how much they made per year, consult a table, and fine them accordingly.
The police hated it, because they were constantly lied to about
how much people made. They recently developed new high-tech tools
for calculating traffic fines and motorists began protesting and
complaining about the prices. They thought it wasn't fair that
they were charged on their gross income instead of their net
income. So, in 1999 the government made major changes, including
basing fines on net income.
The biggest change was that the police can use their cell phones
to tap into official public records and find out motorists’
income. The changes have allowed for fines to be more accurate,
much to the dismay of the motorists.