Labradors are not thief-proof. Labradors are naturally friendly, very friendly to people and not aggressive. So even if a stranger approaches, the Labrador will not attack the stranger. Labradors also cannot be trained to pounce and can suffer from mental illness as a result of that training. Which dogs can be more alert against thieves are German Shepherds, Alaskans, Rottweilers, etc. These dogs are closer to their owners and people at home and are more alert to strangers.
