I used to work around cops,in the place where they had there coptors and THE dogs,they also trained them at that location,you would be supprized how many cops smoke weed,and trust me when they find it growing some where like while haveing the coptors out,twice aday for 1 hour,it dont always make it back to the station,lol.The dogs hardly every really stop working unless there tired or there in a family setting,2 of the k9 officers actully took there dogs home at night,in order to get them relaxed,they stayed in there houses with there kids and everything,the rest of the dogs stayed in there kennels,and you could tell they wernt happy about it.if the dog smells something he will alert.even if hes not working.,so the other guys right,,not to smart,unlesss the cops very cool.those dogs are bread and trained 100,s of hours,sometimes 1000s of hours.