Government Tossing Child Porn Cases Rather Than Discuss Its Torrent-Tracking Software In Court

Legal Issues

from the escape-hatches-and-opacity dept

The federal government isn’t done tossing cases rather than let defendants have access to slightly more level playing field. A new investigation by ProPublica has uncovered more dismissed prosecutions due to the government’s unwillingness to allow defendants to examine the software used to build cases against them.

The cases deal with child porn and BitTorrent distribution. The defendants are hardly the most sympathetic. But, like the cases that exposed the FBI’s use of malware to gather identifying information from devices around the world, child porn investigations are on the front line of the government’s tech deployments. From the description of the cases covered here, it almost appears the government had enough evidence to see the prosecution through to the end. It just chose not to because continuing the cases would mean turning over info on their tracking software to the accused.

Using specialized software, investigators traced explicit child pornography to Todd Hartman’s internet address. A dozen police officers raided his Los Angeles-area apartment, seized his computer and arrested him for files including a video of a man ejaculating on a 7-year-old girl. But after his lawyer contended that the software tool inappropriately accessed Hartman’s private files, and asked to examine how it worked, prosecutors dismissed the case.

Near Phoenix, police with a similar detection program tracked underage porn photos, including a 4-year-old with her legs spread, to Tom Tolworthy’s home computer. He was indicted in state court on 10 counts of committing a “dangerous crime against children,” each of which carried a decade in prison if convicted. Yet when investigators checked Tolworthy’s hard drive, the images weren’t there. Even though investigators said different offensive files surfaced on another computer that he owned, the case was tossed.

The secrecy in these cases is being aided and abetted by private companies. A nonprofit called the Child Rescue Coalition produces a suite of tools called the Child Protection System. But as ProPublica points out, the details are more complicated than its initial appearance: a kindhearted nonprofit helping law enforcement catch child porn producers and consumers. CRC has ties to TLO, a data brokerage recently acquired by credit reporting agency, TransUnion.

Defendants have asked prosecutors to turn over information about CRC’s software in cases where it appears to have possibly drawn the wrong conclusions about downloading and distributing child porn. In those cases, TLO — not the CRC — has stepped in to inform the courts that it will not be producing the requested info.

The software’s makers have resisted disclosure of its coding. In May 2013, TLO asked a federal court in El Paso, Texas, to quash a subpoena to reveal the software known as the Child Protection System in a child-porn case. The materials sought, they said, “are protected under the law enforcement privilege and trade secrets laws.” After the judge ordered the software produced, prosecutors instead agreed to a plea deal that favored the defendant; he was sentenced to three years he had already served for “transportation of obscene material.

It’s not just private companies pushing prosecutors towards dropping cases. It’s also public institutions. Torrential Downpour — software used to track the sharing of child porn via hash values — was developed by the University of Massachusetts using government funding. When access to code was requested by a child porn case defendant, the university inserted itself into the case to reject the judge’s order to turn over the code.

Its lawyer said in a court document that handing over the software would “destroy its value to the university and its faculty researcher,” citing a $440,000 annual FBI grant. “Releasing it to public view would frustrate public policy and impede law enforcement’s ability to deter peer-to-peer sharing of child pornography,” the lawyer added.

The trove of documents [PDF] ProPublica secured show instances where the evidence prosecutors said they had may not have actually been there, thanks to software or human errors. A recent ruling in favor of letting the defendant have access to Torrential Downpour’s code seems to show the FBI relies more on what the software tells it than it can actually see with its own eyes.

Defendant Gonzales argues that Torrential Downpour is material to his defense because the distribution charges are based on child pornography files that Torrential Downpour purportedly downloaded from his tablet but that were not found on the tablet when it was seized by the FBI. Doc. 25 at 8-9. He has presented an affidavit from his expert, Tami Loehrs, confirming that the files are not on the tablet. Doc. 25-5. Loehrs explains in her affidavit that it is critical to Gonzales’s defense to understand how Torrential Downpour functions in order to determine the program’s reliability and accuracy in identifying files that Gonzales is charged with knowingly distributing. Id. at ¶ 17. She further states that based on her many years of research and testing of peer-to-peer file sharing software, including BitTorrent, she has discovered that all of these programs “contain bugs, they do not always function as intended and the data reported by these applications is not always accurate or reliable.”

[…]

Loehrs explained that, because a torrent is simply a text-file containing the hash values – or “fingerprints” – of the target image and video files, a BitTorrent user who downloads a torrent has fingerprints of the target files, even if he has not yet downloaded them. Id. at 22:14-23:8. Loehrs stated that the actual downloading of the target files occurs only when the client software instructs the torrent to search for those files on the BitTorrent network and download them to a designated folder on the user’s computer. Id. at 23:9-25:3. She further stated that a forensic examination of the device used to download the torrent can determine whether the torrent has been used to download the file, and her examination of Gonzales’s tablet revealed no evidence suggesting that he downloaded the files listed in counts one through eight.

It’s not just defendants’ experts being unable to find the files the government claims they downloaded. Investigators themselves have admitted they can’t find files that Torrential Downpour said the accused accessed. An examination of the software being used to build cases should be allowed, but the entities behind the software won’t allow it and the government is cutting defendants loose rather than giving them a chance to properly defend themselves against these very serious charges. I supposed it ultimately works out for defendants, but it only encourages the government to tip the scales in its favor again when the next prosecution rolls around with the hopes the next defender of the accused isn’t quite as zealous.

Filed Under: bittorrent, child porn, child protection system, defendants, discovery, evidence