"Sniffer" joke

A man had just settled into his seat next to the
window on theplane when another man sat down in the aisle seat
and put his blackLabrador Retriever in the middle seat next to the
man.
The first man looks very quizzically at the dog and
asks why the dog is allowed on the plane.

The second man explained that he is a DEA
agent and that the dog is a "sniffing dog". His name
is Sniffer and he's the best there is. I'll show you once we get
airborne, when I puthim to work."
The plane takes off, and once it has leveled out,

the agent says:
"Watch this." He tells Sniffer to "search".
Sniffer jumps down, walks along the aisle, and
finally sits very purposefully next to a woman for a several seconds.

Sniffer then returns to its seat and puts one paw on the agent's
arm.
The agent says, "Good boy", and he turns to the man
and says: "That woman is in possession of marijuana, so I'm
making a note of her seat number and the authorities will apprehend her when we land."
"Say, that's pretty neat" replies the first man.
Once again, the agent sends Sniffer to search the
aisles. The Lab sniffs about, sits down beside a man for a few
seconds, returns to its seat, and this time, he places TWO paws on the agent's arm.
The agent says, "That man is carrying cocaine, so
again, I'm making a note of his seat number for the police."
"I like it!" says his seat mate.
The agent then told Sniffer to "search" again.
Sniffer walked up and down the aisles for a little
while, sat down for a moment, and then came racing back to the agent, jumped into the middle seat and proceeded to poop all over the place.
The first man is really grossed out by this behavior
and can't figure out how or why a well-trained dog would act like
that, so he asks the agent "What's going on?"
The agent nervously replied, "He just found a bomb!"