[en] We report on an investigation that confronts the lag-luminosity relation (LLR), i.e. a surrogate redshift parameterization based upon an empirically determined anti-correlation between the observed isotropic luminosity and the temporal lag between the arrivals of photon pulses in low (25-50 keV) and high (100-300 keV) energy bands, with observations of gamma-ray bursts (GRBs) with Swift's Burst Alert Telescope (BAT). Our initial methodology is based upon a cross-correlation function (CCF) analysis of 64 ms BAT light curves (temporal spectra), for a small subset of GRBs with observed spectroscopic redshift (z_obs). Our preliminary results span 4 temporal decades and indicate an agreement with LLR, within the margins of error (excluding GRBs 980425 and 060218)