  We present results for an exploratory lattice calculation of the leading
parity-violating pion-nucleon coupling $h_\pi^1$. Based on the PCAC relation we
use a parity-conserving Lagrangian and focus on the techniques to determine the
nucleon matrix elements of the effective 4-quark operators. For our study we
employ an ensemble of twisted mass fermions with $260$ MeV pion mass. Barring
mixing with lower-dimensional operators and renormalization at this stage, we
discuss our estimate for $h_\pi^1$.
