Let's not forget that the FO would have been arrested on suspicion of performing an aviation function at a time when the proportion of alcohol in his breath, blood or urine exceeds the prescribed limit.
Unless he's failed to provide a specimen, he's most likely gone to blood/urine analysis which will take a week or so to get the results.
As we have no idea at the moment if he was over the prescribed limit or not, let's not cast any aspersions until the results are back and let's see if he's charged or not.