Report: FBI investigators overstated evidence against criminal defendants

The Justice Department and FBI formally acknowledged that FBI forensic investigators routinely gave flawed testimony overstating evidence against criminal defendants during the 1980s and 1990s. In more than a dozen cases, defendants were later executed or died in prison. Spencer Hsu of The Washington Post joins Hari Sreenivasan from Washington to discuss.

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    News from Washington tonight that, for nearly two decades, during the 1980s and '90s, top FBI forensic investigators routinely gave flawed testimony, overstating the evidence they had against criminal defendants.

    In more than a dozen cases, the defendants were later executed or died in prison.

    Spencer Hsu broke the story in today's Washington Post. He joins us now.

    So, you said that this is a watershed moment in one of the country's largest forensic scandals. Break this down for us.

  • SPENCER HSU, The Washington Post:

    What has been found has been, as you say, that, for more than two decades, nearly every examiner and nearly every criminal trial in which FBI experts gave testimony against criminal defendants, they overstated the strength or the significance of a match.


    So, you said that about a quarter of all the wrongful convictions, the people who have been exonerated later on, the testimony of hair examiners or bite mark comparisons have actually helped sway juries or judges.


    That's right.

    Out of about 329 DNA exonerations, a quarter, more than a quarter have involved invalid forensic science. One of the issues here is that, unlike DNA, which has a — was developed, you know, by scientists for scientists, a lot of the earlier pattern-based techniques, comparing hair, fiber, bite marks, even tracing bullets to — being fired from specific weapons, were developed in the lab by law enforcement.


    Let's just say, for example, if a defense attorney figures out that some of the evidence used in a trial for their client includes testimony from one of these FBI inspectors, what happens to them?

    Does this mean that the judge automatically grants a new investigation or a retrial?


    Not necessarily.

    The FBI has offered to retest, in cases where errors were made, DNA, if DNA evidence is available. The federal government has offered to drop procedural bars to post-conviction appeals as well.

    But, for states, most states make it difficult to challenge old convictions in the absence of DNA. Only California and Texas have laws that permit it in cases when forensic evidence is recanted or undermined by scientific advances.


    What is the FBI going to do to fix this?


    They have said that they will do a root cause analysis after all the reviews are completed. Again, they have offered to retest DNA, when DNA evidence is available, and to allow federal cases to be brought.

    They are agreeing to review scientific testimony and lab report standards to make clear what is erroneous and what is acceptable in 19 other techniques. They say they did this for hair in 2012, when our reports surfaced and they launched this review.

    The ball now again goes to state authorities, as well as to the courts, to determine if they will change these precedents, more rigorously challenge the admissibility of scientific evidence.


    All right, Spencer Hsu of The Washington Post, thanks so much.


    Thank you.

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