  An intriguing result of statistical mechanics is that a first-order phase
transition can be rounded by disorder coupled to energy-like variables. In
fact, even more intriguing is that the rounding may manifest itself as a
critical point, quantum or classical. In general, it is not known, however,
what universality classes, if any, such criticalities belong to. In order to
shed light on this question we examine in detail the disordered three-color
Ashkin-Teller model by Monte Carlo methods. Extensive analyses indicate that
the critical exponents define a new universality class. We show that the
rounding of the first-order transition of the pure model due to the impurities
is manifested as criticality. However, the magnetization critical exponent,
(\beta), and the correlation length critical exponent, (\nu), are found to vary
with disorder and the four-spin coupling strength, and we conclusively rule out
that the model belongs to the universality class of the two-dimensional Ising
model.
