The FBI lab's backlog has grown as federal DNA collection laws expanded in recent years. Since a new law went into effect earlier this year, the lab has been receiving samples from anyone arrested for a federal crime. The new law also ordered federal agents to take DNA samples from people they detain, typically immigrants suspected of being in the United States unlawfully. Unlike the other labs we are following, the FBI releases its data only on a quarterly basis.

What they are doing about it: The lab is using new robotic systems that will eventually allow it to process 120,000 samples every month, a spokeswoman said.

LAPD has one of the largest backlogs in the country. (See here for our coverage of LAPD's backlog troubles.) The statistics provided to us by LAPD are only for unprocessed rape kits — DNA samples taken from arrestees or convicts are processed by the California Department of Justice Crime Lab.

What they are doing about it: LAPD began chipping away at its backlog in January after hiring more lab technicians and outsourcing scores of rape kits to private labs for testing. The department hopes to reduce its backlog within four years.

The California DOJ's lab has one of the largest DNA backlogs of any state lab. Its backlog has boomed since Prop. 69, which mandates DNA collection from arrestees, went into effect in January 2009.

What they are doing about it: A spokesman with California’s Department of Justice says that at any given time 30,000 of its samples can be classified as "in process." The state has also been hiring more scientists and might eventually outsource samples to private labs, a lab official said. The lab presently has no target date for reducing the amount of unprocessed evidence.

In May, the Illinois legislature narrowly defeated a bill that would have mandated DNA collection from arrestees. That bill could be reintroduced soon, but the state presently has no backlog of DNA samples collected from arrestees or convicts. Meanwhile, a state audit found that the lab reported bogus DNA backlog numbers for several years, leading former Gov. Rod Blagojevich to wrongly declare in 2005 that the backlog was eliminated.

What they are doing about it: The lab is using several methods to cut into the backlog, including hiring more scientists and using robots to speed the testing process. The lab estimates that a scientist using a robot can analyze more cases in about one week than a scientist working manually can analyze in a couple months.

Note: This lab does not have an "offender" backlog.

Virginia's government was among the first to require DNA samples from arrestees and has no arrestee sample backlog. Advocates for expanded DNA testing point to the Virginia lab as a model: a lab that can handle samples from wide swaths of the population where the arrestee samples are prioritized so they can be analyzed before a suspect is released. Its case backlog includes several dozen cases in a Virginia post-conviction DNA testing project that involves decades-old evidence. The program's goal, a lab spokesman said, is to identify people who may have been wrongfully convicted.

What they are doing about it: The lab doesn't have a target date for eliminating the backlog. A spokesman said the lab is working "consistently to minimize the number of cases affected so we can best serve the citizens of the Commonwealth."