The observed brightness of Type Ia supernovae is affected by gravitational
lensing caused by the mass distribution along the line of sight, which
introduces an additional dispersion into the Hubble diagram. We look for
evidence of lensing in the SuperNova Legacy Survey 3-year data set. We
investigate the correlation between the residuals from the Hubble diagram and
the gravitational magnification based on a modeling of the mass distribution of
foreground galaxies. A deep photometric catalog, photometric redshifts, and
well established mass luminosity relations are used. We find evidence of a
Jonsson, J. et al. 2010, MNRAS, accepted, astro-ph/1002.1374
