If properly trained, dogs can be the best guards. Even if something or someone does not appear to be a threat, it only takes them seconds to analyze your emotions and expressions to determine their true intention.

Dubai, a Great Dane, was one of those dogs. Dubai mistook this intruder for an unknown friend when he entered Tracy’s home. While Dubai was inspecting this new scent, the man petted the dog. But, seeing him calm and loving, Dubai assumed he posed no threat. As a result, he let him in.

Intruder breaks

Dubai doesn’t realize what’s going on until Tracy comes out and notices the intruder. Dubai went into defensive mode after she screamed. He launched a barrage of snapping and barking at the man, chasing him out the door.

Watch the full video here:

So, lock your doors and let your dog loose. And don’t forget to SHARE this video to your friends and family.