Houston police evidence lockers are filled to the brim, including backpacks, ATMs, thousands of bicycles, notes from a nearly century-old homicide case and an infestation of rats that have been feasting on drugs. “We got 400,000 pounds of marijuana in storage that the rats are the only ones enjoying,” Houston Mayor John Whitmire said, vowing to organize — and where feasible, discard — 1.2 million pieces of evidence held by the city, the Washington Post reports. Although crowded evidence lockers are a problem police departments nationwide struggle with, legal experts warn that the urge to throw out old evidence should be tempered, because one never knows what could be useful for future investigations and as forensic technology advances. Allowing seized narcotics to pile up can also threaten the troves of more valuable evidence by attracting pests, said Peter Stout, who leads the Houston Forensic Science Center. “They’re edible, they’re tasty, they’re all kinds of things. You can’t store large quantities of drugs without expecting some of these things to happen,” Stout said, adding that the Houston police also have hired exterminators. “But this is difficult getting these rodents out of there. … They’re drug-addicted rats. They’re tough to deal with.”
Whitmire will work with the Harris County District Attorney’s Office to discard narcotics evidence obtained before 2015 that no longer has any value. “So much evidence is kept and stored that is no longer needed, that has no impact on the resolution of that charge, that conviction or even that innocence,” Whitmire said.
Burning old drugs could incur costs in the hundreds of thousands of dollars, because it must be done in accordance with environmental guidelines, Police Chief J. Noe Diaz. The district attorney’s office said it had completed its first burn of 15,000 pounds of narcotics on Thursday. “It costs a lot of money to destroy illicit narcotics, and so the DA’s office is going to utilize funds that we control to help the city with this immediate problem,” Harris County District Attorney Sean Teare said. The broader question of whether and when any piece of evidence should be discarded — and generally, how to store old evidence — is a tricky one. Overcrowded or pest-infested evidence rooms affect police departments across the nation, Stout said. In the past, fires in these storage facilities, which are crowded with flammable materials, have compromised evidence in Kansas City, Minneapolis and New York. When flames engulfed a police warehouse in Brooklyn in 2022 and ruined evidence in many unsolved cases, attorneys and city officials expressed concern about the department’s broader preservation rules. Richard Friedman, an expert on evidence and a law professor at the University of Michigan, advised against any rule that would automatically throw out evidence after a certain number of years, adding that there should be some consideration of the particular case. “It seems to me that as long as that person is alive, the evidence ought to be maintained,” he said.