  We study the SO(3) lattice gauge theory in 3+1 dimensions with the adjoint
Wilson action modified by a $\mathbb{Z}_2$ monopole suppression term and by
means of the Pisa disorder operator. We find evidence for a finite temperature
deconfinement transition driven by the condensation of U(1) magnetic charges. A
finite-size scaling test shows consistency with the critical exponents of the
3D Ising model.
