The rodents are enjoying marijuana at the Houston Police Department that has been sitting in evidence for years.

"We've got 400,000 lbs. of marijuana in storage, that the rats are the only ones enjoying it," said Houston Mayor John Whitmire.

To illustrate the problem, Houston police Chief J. Noe Diaz pointed to one piece of cocaine evidence from 1996 that was still in the lockup. The individual tied to the drugs pleaded guilty, was sentenced to 20 years in prison and has since been released, he said.