He also explains that a handkerchief in package contained the scent of rabbit blood and cocaine, to attract the dogs so when they sniffed it, the cocaine would temporarily numb the German dogs' sense of smell.
A handkerchief in package contained the scent of rabbit blood and cocaine. This was to attract the dogs so when they sniffed it, the cocaine would temporarily numb the German dogs' sense of smell. This is what he explains.