An unintentionally hilarious investigation into the effectiveness of guard dogs finds that if you're a loving pet owner, your dog probably can't be counted on to stop intruders.

CBS Atlanta teamed up with some local dog owners and a professional dog trainer to see if burglars have much, if anything, to fear. The station enlisted the help of Jeff Schettler, who runs the Georgia K9 National Training Center.

Schettler dressed in a 40-pound protective suit and entered each dog owner's home, simulating a burglary. And unfortunately for the dog owners, had Schettler been a real criminal, he would have made it out safely in every single attempt.

"Even when they are in their own home, they can be a bit nervous," he told the station.

And even when they aren't nervous, they might just be downright friendly. For example, Star, a 10-pound papillon mix, let Schettler cradle her in his arms and carry her outside the home.

The other guard dogs in the test included a 38-pound Brittany spaniel named Calico; a 29-pound English Staffordshire terrier (aka, pit bull) named Bindi; an 85-pound Rottweiler named Roxie; and Kevlar, a 100-pound German shepherd.

If you guessed the pit bull would be the most ferocious, you'd be dead wrong. In fact, Bindi performs tricks for Schettler when he enters her home, repeatedly waving her front paw in his direction and licking his face.

Kevlar puts up the most resistance, nipping at Schettler's legs when he heads upstairs to the area that contains the dog's kennel. But even then, Kevlar quickly retreats, running back downstairs and leaving Schettler to go about his business.

You can watch the full series of guard dog test videos below:

Several people have offered their own list of breeds that make the best guards. But Schettler says it has more to do with how the owner has raised the animal and how it has been trained. A number of locations around the country offer guard dog rental services to paying customers.