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Indiana Court Rules Melted Down Hard Drive Not Destruction of Evidence

Posted by samzenpus on from the it's-getting-hot-in-here dept.

An anonymous reader writes An Indiana court has ruled that a hard drive that was sent to recycling was not destruction of evidence. The ruling stems from a BitTorrent file-sharing case filed by Malibu Media where a defendant claimed that his hard drive had failed thanks to heavy use. Malibu claimed that the act was destruction of evidence and filed a motion demanding a default judgement. The court denied this motion suggesting that because the hard drive failed, there was no evidence to destroy in the first place.

44 of 181 comments (clear)

  1. Hello microwave by Anonymous Coward · · Score: 4, Funny

    Hello microwave. I'd like you to meet hard drive.

    1. Re:Hello microwave by Anonymous Coward · · Score: 2, Informative

      Hello microwave. I'd like you to meet hard drive.

      Perhaps you intended your comment to be a joke, but in case anyone believes
      a hard drive can be destroyed such that data cannot be recovered from it
      by "cooking" the hard drive in a microwave, it should be explained that
      a platter-type drive will NOT be destroyed by "cooking" it in a microwave.

      The microwave, however, WILL be severely damaged.

    2. Re:Hello microwave by ssufficool · · Score: 3, Informative

      Actually a single overwrite with zero is recoverable on older non-PMR drives by simply realigning the heads a bit to catch the edge of the magnetic track only weakened by the zero wipe (and I mean a very small bit) and re-installing the drive. On PMR, there are actually weak bits left after a zero wipe that are recoverable by equipment capable of reading weak bits. A random wipe is usually effective in all cases. A hammer leaves nothing to chance.

      I also don't understand how a drive can be ruled as evidence if nothing is yet discovered on the hard drive. I don't understand how the prosecution can ask for a default judgement without solid compelling evidence of a crime. Without a discovery of the drives contents I'm assuming they had other evidence.

    3. Re:Hello microwave by Immerman · · Score: 2, Interesting

      Depends on just how motivated someone is to recover the old data. The hard drive itself will almost certainly be unable to read the previous data after a single overwrite, but remove the platters and install them in a machine specifically designed to read the edge of the tracks, which as a rule *aren't* overwritten, and most of the data can generally be recovered easily enough. (Since head placement is imperfect, every recording of a track writes to a slightly different path, leaving the previous N recordings partially untouched)

      Granted, there's going to need to be suspicion of some pretty important data on that hard drive for it to be worth the trouble, but if there has ever been data on a drive that may be of sufficient interest to someone with the resources to recover it, then you absolutely need to do multiple overwrites with random noise to ensure it can't be recovered. And/or physically destroy the platters by melting, not shattering (though that would probably have to be some *really* important data to be worth reconstructing a shattered platter)

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    4. Re:Hello microwave by geoskd · · Score: 5, Informative

      From what I understand, all it takes is one knock with a hammer to ensure platters are bent and can never be used again. And there is no known practical method to restore data after a single overwrite with 0s. Everything else is pure paranoia.

      Overwriting with 0s will not perfectly overwrite the tracks. There is some slop on the read head positioning that will normally allow enough data to be recovered that the ECC can be used to rebuild the full data set. This can only be done by taking the platters out and putting them into a machine that is purpose built for the task of recovering such data. Having worked on part of the design of such a machine, I can tell you two things about it: First, it exists, and second, it is not cheap. I was told the cost of the one I worked on was $12M USD.

      Physically deforming the platters will make the job much more difficult (expensive), but not impossible. A combination of clever chemistry and an electron microscope can usually recover data off a mangled platter. This process sucks because it has to be done by hand, but if its worth enough to you, there a couple of labs around the country that can handle that level of data recovery. A better way to ensure total destruction is to melt the platters outright. not only does the melting deform the platters, but sufficient heat will thoroughly destroy the data, even if the platter does not completely melt.

      --
      I wish I had a good sig, but all the good ones are copyrighted
    5. Re:Hello microwave by tibit · · Score: 4, Insightful

      older non-PMR drives

      Those drives are now museum artifacts, so your concern is of no practical use. No mainstream 2.5/3.5 in. hard drive manufactured in the last 15 years is recoverable after a zero-out.

      --
      A successful API design takes a mixture of software design and pedagogy.
    6. Re:Hello microwave by tibit · · Score: 4, Informative

      most of the data can generally be recovered easily enough

      Nope. The drives manufactured in the last two decades, give-or-take, have the size of magnetic domains matched to the size of the field generated by the heads. The "edge" of the track is defined by where data from one track ceases to be, and the data from another track begins, and this is a binary thing. One domain here has data from this track, another domain there has data from that track.

      What people constantly fail to realize is that if there was an area of disk, the mythical "inter-track gap", that was any good at storing any data, it'd be stupid for the manufacturer to not put the expensive platter real estate to good use. And they do precisely that: they use all of the platters to store your current data. There is no inter track gap.

      --
      A successful API design takes a mixture of software design and pedagogy.
    7. Re:Hello microwave by Immerman · · Score: 3, Informative

      If they could reliably position the heads in *exactly* the same place every time that would be the case. But they can't - mechanical devices and perfection are mutually incompatible. So assuming there's an error of +/- N um in head positioning, your track has to be at least 2*N um wider than the recording head to avoid partially overwriting adjacent tracks. You can cut that roughly in half by sharing the buffer zone between adjacent tracks - hence creating the " inter-track gap". Modern drive heads are are more precise than they used to be, but that only reduces the width of the necessary buffer zones, it doesn't eliminate them entirely.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    8. Re:Hello microwave by Jane+Q.+Public · · Score: 5, Informative

      I don't understand how the prosecution can ask for a default judgement without solid compelling evidence of a crime. Without a discovery of the drives contents I'm assuming they had other evidence.

      First, part of the reason you don't understand this is because you are under the impression that copyright infringement for personal use is a crime. It is NOT. This is a civil matter, not criminal.

      Generally speaking, copyright infringement is only criminal if you are doing it in bulk for profit. Historically, that meant what has been known legally for about 100 years as copyright piracy, which again in general refers to making unauthorized copies of copyrighted works and selling them.

      It is today's media industry which has deliberately attempted to confuse you by labeling downloads of copyrighted material for personal use piracy. It is not. Piracy is a legal term referring to PROFITING from unauthorized copying of copyrighted works.

      Now, back to the case at hand: being a civil matter, and not criminal, the court need not require probable cause in order to demand that evidence be produced (although it probably can't be seized beforehand. However, because of this, people have been known to destroy evidence after being served notice of a lawsuit. If they do that for the purpose of hiding the evidence, and the plaintiff can show that, it may be ruled spoliation of evidence, and could result in a summary judgment in favor of the plaintiff.

      But despite this not being a criminal matter, plaintiff still bears the burden of showing that spoliation happened, via genuine evidence. In this case, plaintiff's claim of spoliation was not backed by evidence; it was a claim without substance. Defendant had a reasonable explanation for the drive's demise, and plaintiff could not show otherwise.

      I also don't understand how a drive can be ruled as evidence if nothing is yet discovered on the hard drive.

      Remember that this is a civil matter. Standards of evidence are different. If a reasonable person would believe that the drive contained evidence, a judge might ask that it be produced. It very much depends on the circumstances.

    9. Re:Hello microwave by Anonymous Coward · · Score: 2, Interesting

      older non-PMR drives

      Those drives are now museum artifacts, so your concern is of no practical use. No mainstream 2.5/3.5 in. hard drive manufactured in the last 15 years is recoverable after a zero-out.

      Of course, an extra few words explaining that due to areal density on drives larger than 15 GB the chances of recovering a single 32-bit number from a zeroed drive is less than three percent would make you seem less like a dick spouting such an assertion. Residual magnetism used to be the way they recovered data from a zero out, but due to how tiny the bits are on the media these days it's not possible to do that, even after a single pass of zeroes.

      Melting is a new one for me, but quite effective I am sure. Me, I still prefer a drill press, much more physically satisfying and environmentally friendly. And yes, I have applied power to the drive so the platters shatter and shred when I do it. Just make sure you clamp the drive down first. He he

    10. Re:Hello microwave by thegarbz · · Score: 4, Informative

      When did you do this? Data densities have gotten so tight and tolerances so small that while I won't call bullshit on your statement I will call it out of date. It's impossible to recover data at this day and age. While you're right that the head doesn't perfectly write over the track, the gaps between the tracks are so small that the magnetic field is not sustainable when something is written. Heck one of the challenges the industry is facing is writing a track without having the tracks either side break down, and you're taking about a sustained field an order of magnitude smaller.

    11. Re:Hello microwave by citizenr · · Score: 2

      BULLSHIT, name ONE lab and ONE documented recovery from single overwrite

      --
      Who logs in to gdm? Not I, said the duck.
    12. Re:Hello microwave by stoatwblr · · Score: 2

      The Peter Gutman paper which talks about data recovery on hard drives by reading track edges and relying on imprecise positioning was performed on 20Mb MFM and RLL stepper motor hard drives (the kind which needed to be "parked" before switching off. These _are_ serious museum pieces which always had a bit of mechanical "slop" in the gearing/steel band mechanisms which actually drove the head position.

      All drives greater than 200Mb use variable sector geometry, so track layout is nowhere near as predictable and beyond that point the track density is such that it could take _years_ to recover one drive, if it's possible at all.

      Voice coil hard drives use continuous feedback mechanisms to ensure the heads are centred, resulting in a much higher positioning accuracy than can ever be obtained from stepper-motor-based systems.

      Gutmann himself wrote a followup several years later stating that the DoD overwrite procedure was largely irrelevant to voice-coil based drives and that a single security wipe was more than sufficient in any drive manufactured past about 1996. He was sick of it being used as some kind of voodoo when it didn't matter anymore.

    13. Re:Hello microwave by X0563511 · · Score: 2

      I see your 62-grain 5.56 and raise it a 180-grain 7.62 :P

      --
      For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
  2. I disagree... by Anonymous Coward · · Score: 4, Insightful

    ...without knowing how the drive "failed" the court cannot prove that there was no evidence to destroy. I guess he never heard of drive recovery places that can recover some information from a majority of drives that "fail"

    1. Re:I disagree... by wiredlogic · · Score: 5, Interesting

      That requires the plaintiff to spend money to have the analysis done which isn't part of the copyright extortion business plan.

      --
      I am becoming gerund, destroyer of verbs.
    2. Re:I disagree... by AchilleTalon · · Score: 5, Informative

      You should have read the article. The argument is about what the defendant knows and the intention. The drive was sent to recycle BEFORE the defendant even knows a litigation is imminent. Hence, it is not possible to argue the defendant destroyed an evidence while he didn't know it was to become an evidence. The hard drive was destroyed in good faith by the defendant without an intention to interfere with legal procedures since there wasn't any at the time and he wasn't even aware any was eminent.

      --
      Achille Talon
      Hop!
  3. Wow - interesting by xystren · · Score: 4, Insightful

    Lots of room for potential abuse, but an interesting judgement. I wonder if there will now be laws stating that dead hardware must be kept beyond the statute of limitation in case a lawsuit ensues. So what about all those "catastrophic failures" right before the suit if filed? A double edged sword none the less.

    1. Re:Wow - interesting by AchilleTalon · · Score: 2

      There is no room for abuse. You haven't read the article or didn't take enough attention to the argument. If the defendant had destroyed the hard drive while the lawsuit was proceeding or even with the intention to destroy evidence knowing a lawsuit was imminent, the outcome would have been completely different. The defendant's ass was saved because the hard drive was destroyed or sent to recycle BEFORE any lawsuit and BEFORE he even knows a lawsuit is imminent.

      --
      Achille Talon
      Hop!
    2. Re:Wow - interesting by Anonymous Coward · · Score: 2, Informative

      It was destroyed before he knew that he was named as a defendant in the lawsuit. The only thing he knew from the Comcast letter was that they had received a court order arising from a lawsuit to hand over logs and customer information associated with an ip address on specified date(s). The letter did not say he was a party to the lawsuit (that happen Nov., but he had still not been officially notified) and only contained Comcast's notification to their customer that they would comply with the court order. It imposed no legal instructions on the guy, it was mostly just a CYA courtesy by Comcast. Only a legal instruction included in the official court summons to the defendant or a letter from the plaintiff's attorneys could have ordered him to preserve evidence by ceasing to use the drive and to remove it from his computer. The plaintiff didn't communicate with the defendant until he was served 7 months after he received the initial Comcast letter.

  4. How is this supposed to work...? by Anonymous Coward · · Score: 2, Interesting

    - person uses drive for illegal activity
    - police raids and collects drive
    - somehow drive gets destroyed by 'person'?

    Or the other way around:
    - person uses drive for illegal activity
    - drive gets destroyed by 'person'
    - police raids and collects broken drive

    Does this imply that it is illegal to destroy any evidence while doing criminal activities? e.g., illegal to wear gloves to avoid finger-prints when murdering people?

    1. Re:How is this supposed to work...? by Em+Adespoton · · Score: 5, Informative

      - person uses drive for illegal activity
      - person receives DMCA notice
      - person "catastrophically fails" their drive
      - person receives subpoena
      - person notifies court that sole evidence no longer exists due to drive failure.

      Hence, your assumptions are flawed (for this case).

      The ruling found that it was NOT illegal to destroy evidence before it is called for evidence. It is illegal to intentionally destroy evidence that has been called for by the court. There are also retention laws that cover certain situations. Setting data retention guidelines prior to the suit protects you from getting into this mess (if you can prove that you ALWAYS destroy your data after X days/ x failed writes/ etc. then you're not culpable if you do what you always do just prior to being served).

  5. Melted down hard drive by rossdee · · Score: 2

    Since when do they melt down hard drives?

    I thought they had to be carefully taken apart and the toxic materials removed to the special areas so they don't contaminate the environment.

    1. Re:Melted down hard drive by Anonymous Coward · · Score: 2, Informative

      They go through a shredder, and then toxic chemicals are used to extract gold, then it gets sorted in aluminium, steel, and copper. (I suppose everything not of value is dumped)

  6. Uninformed court? by drhamad · · Score: 2, Insightful

    That seems like a weird decision... I mean, even if the drive itself has failed it doesn't mean the platters have no data on them that could be recovered. Of course, the secondary question is whether the destruction was intentional or not, but as for the question at issue here, I don't see how a court could say that there is no evidence that was destroyed. The likelihood is completely opposite.

    --
    -Daniel
  7. Presumption of innocence by aepervius · · Score: 4, Insightful

    "without knowing how the drive "failed" the court cannot prove that there was no evidence to destroy."

    correct me if I am wrong, but AFAIR the US justice system, It is up to the prosecution side to prove there was evidence on teh HD, not on the side of the defense there was not. Therefore from the court in absence of proof of existence of evidence, the assumption should be by default there was no evidence. IF the prosecution has proof tehre was evidence they are free to provide them. But until then by presumption of innocence, the court has to assume the recyclage was lawful. Otherwise if the presumption was it was destruction of evidence, then it amounts of a presumption of guiltiness.

    --
    C. Sagan : A demon haunted world:
    http://www.amazon.com/gp/product/0345409469/
    visit randi.org
    1. Re:Presumption of innocence by SuricouRaven · · Score: 3, Informative

      Close. This was a civil case, so the plaintiff doesn't need to prove anything beyond a reasonable doubt, as the prosecution would in a criminal case. Only has to prove that he was probably infringing.

    2. Re:Presumption of innocence by CaptainDork · · Score: 4, Informative

      Not this.

      The accused is not bound to preserve any and all possessions that might be discoverable in litigation at a later date after even a rumour that the accused will become a party in a suit.

      Evidence does not exist before probable cause defines the scope of what will constitute evidence, only after a motion to preserve evidence is filed.

      --
      It little behooves the best of us to comment on the rest of us.
    3. Re:Presumption of innocence by doubledown00 · · Score: 4, Insightful

      Well, it's a little more than "probably". They have to show a preponderance of evidence. It's not enough to say, "this guy's a big movie fan and had 200gig of downloads every month and never rented a movie or went to a theater, so he probably was pirating movies".

      Preponderance of the evidence is a 51 percent standard......i.e. "more likely than not".
      Barring any statutorily necessary elements of the Plaintiff's claims, if the jury finds that to be sufficient then the dude can be found liable. It's all circumstantial, certainly. But I have guys doing decades of prison time based on circumstantial evidence, and that was "beyond a reasonable doubt". With what you lay out above, I could *easily* see a jury making a few key inferences and finding liability in that.

      Never try and predict what the 12 geniuses in the box will or will not do.

    4. Re:Presumption of innocence by AmiMoJo · · Score: 4, Informative

      I bothered to RTFA and you are both a little way off what actually happened.

      The guy received notice of the lawsuit. Five months later, the drive failed and he threw it away. The court concluded that because five months had passed it was unlikely he was trying to destroy evidence; if that had been the goal he would have done it sooner.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
    5. Re:Presumption of innocence by hackwrench · · Score: 2

      The article said he received some sort of copyright notice from Comcast before the hard drive failed but only received notice that he was a party to a lawsuit after it failed.

    6. Re:Presumption of innocence by Anonymous Coward · · Score: 2, Informative

      The redefinition of the word "piracy" is not natural evolution though, it's a deliberate attempt by copyright maximallists to prejudice courts and pressure Congress.
      Yes, language changes. But corruption and manipulation should be resisted.

    7. Re:Presumption of innocence by Hydian · · Score: 2

      Pirating is copying or capturing ships on the high seas.

      Nothing strikes terror in even the most hardened crew like seeing a giant Xerox machine sailing towards them flying the Jolly Roger.

  8. Did the court say that? by 91degrees · · Score: 2

    The court denied this motion suggesting that because the hard drive failed, there was no evidence to destroy in the first place.

    Okay I skimmed the article, but I couldn't find a comment suggesting that.

    It seems more that there's no evidence that the defendant wilfully destroyed evidence. The plaintiff wanted the court to assume that there was harmful evidence on the hard drive, simply because the defendant had thrown it out. The defendant on the other hand threw it out simply because it was dying, and had no idea that it might be relevant in the litigation.

  9. Pretty Fine Line There by Greyfox · · Score: 4, Informative

    Basically it works out that he'd recycled the drive prior to being aware that he personally was being sued for copyright infringement. He also didn't run out and recycle all his drives as soon as he got a letter from Comcast saying that some sort of lawsuit was in progress. I assume the guy had some evidence to back up the dates in his claims. There's no discussion about whether they asked him for the backups he had or anything. In a nutshell, I wouldn't want to have to bet my ass on the court coming to the conclusion it did in any particular case.

    --

    I'm trying to teach myself to set people on fire with my mind... Is it hot in here?

    1. Re:Pretty Fine Line There by Solandri · · Score: 2

      Basically it works out that he'd recycled the drive prior to being aware that he personally was being sued for copyright infringement. He also didn't run out and recycle all his drives as soon as he got a letter from Comcast saying that some sort of lawsuit was in progress. I assume the guy had some evidence to back up the dates in his claims.

      You have this backwards. The accused is presumed innocent until proven otherwise (the wishes of copyright holders notwithstanding). The burden of proof is thus upon Malibu Media to prove he knew about their intent to sue before he had the drive recycled.

      Personally I would say a mailed notice from Comcast is insufficient - lots of us have gotten those, whether correctly or in error, and nothing has happened. So it's insufficient to act as a notice to preserve evidence. I'd say a certified notification letter which must be followed through with an actual lawsuit or settlement is the minimum. Another party should not have the power to compel me to modify my behavior (hang onto equipment I'd otherwise throw out) for the mere cost of a 49 cent stamp.

  10. Re:Kill-ur-drive contest? by Bob9113 · · Score: 2

    If the goal is to kill a drive, there's a much faster way. Pull it out of the case, but keep the wires connected. Shut down the machine. Turn the machine back on. When the drive is just starting to spin up, slam it flat on the desktop.

    Before the platters are up to speed, there is very little Bernoulli force holding the heads up. The above operation will crash the head and leave a nice big scratch.

    --
    Stop-Prism.org: Opt Out of Surveillance
  11. Re:Kill-ur-drive contest? by gnasher719 · · Score: 3, Informative

    Before the platters are up to speed, there is very little Bernoulli force holding the heads up. The above operation will crash the head and leave a nice big scratch.

    And then your opponent finds an expert witness who examines the hard drive, finds the scratch, and explains to the court that it was most likely intentionally damaged. They don't need proof, just likelihood. And now you are stuck, because whatever your opponent claimed is on the drive, the court now assumes it was there before you destroyed it.

  12. Court made the right decision by Anonymous Coward · · Score: 5, Informative

    I know this because I RTFA'd

    Defendant received notice of this lawsuit at the beginning of October 2012. []Defendant, however, did not destroy the hard drive until “late February 2013.” [] Thus, almost five months passed between the time that Defendant learned of the lawsuit and Defendant’s destruction of the hard drive. Had Defendant truly wished to hide adverse information, the Court finds it unlikely that Defendant would have waited nearly five months to destroy such information. Instead, Defendant’s continued use of the hard drive for the months after he learned of the litigation suggests that the hard drive contained no information to hide at all, or that Defendant did not intend to hide any such information.

    The timing of Plaintiff’s amendment and the service of its complaint also detract from an inference of bad faith. Plaintiff amended its complaint to add Harrison as a Defendant on November 9, 2012. [] Plaintiff, however, did not serve the amended complaint on Harrison until April 2013, [], after Defendant had arranged to order the replacement hard drive, [], and after the recycling of Defendant’s hard drive. [] Furthermore, Defendant testified that the service of the complaint was the first time that he became aware that he was personally being sued for copyright infringement. []

  13. Which is how it has always worked by Sycraft-fu · · Score: 2

    Same deal with physical evidence. As an individual, you generally have no records retention requirements. You are welcome to destroy your stuff as pleases you. So you can shred bills, old receipts, etc as soon as you want. None of this is destruction of evidence if you get sued. When it changes is if you get sued, and you are told to keep things, and you then destroy it. Then you are in trouble. So if a court case happens, the court can, and will, say "You need to keep anything related to this around in case we want to see it." But just in your everyday life you can wipe drives, shred documents, etc as you please.

    This can be a little difference if we are talking something related to a business, there are more records retention requirements for various businesses, but again it has to be something where there is a legal requirement to retain it.

    The only other case would be if something goes against policy. If a business has a policy that all old harddrives are kept in storage for 10 years before being destroyed, that's not legally required but they can do it anyhow. However if a lawsuit happens and the one harddrive that was asked for just so happened to be sent off to be destroyed immediately, against the business' own policy, well then that could be trouble.

    You don't have to retain everything for all time just in case someone wants it for a lawsuit. However if you have something, and a court says it is evidence, you then have to retain it until the court is done with it.

  14. Malibu Media by koan · · Score: 5, Interesting

    Magistrate Judge Stephen L. Crocker didn't like this tactic. He froze eleven of Malibu's cases in western Wisconsin, and ordered Malibu's lawyer to explain why she shouldn't be sanctioned for violating court rules. Filing paperwork with the Court with no purpose except to harass or embarrass an opponent is a big no-no. Judge Crocker wondered why Malibu would file a list of movies with embarrassing titles that Malibu doesn't own and can't sue over.

    https://www.eff.org/cases/mali...

    --
    "If any question why we died, Tell them because our fathers lied."
  15. Just an FYI: who is Malibu Media: by Kubla+Kahhhn! · · Score: 2

    Infamous porn copyright troll, using humiliation of public exposure as a tactic.

  16. If it's good enough for the IRS... by KermodeBear · · Score: 2

    ...then it is good enough for us. Right?

    --
    Love sees no species.
  17. over write once and be done with it by Anonymous Coward · · Score: 3, Insightful

    From what I understand, all it takes is one knock with a hammer to ensure platters are bent and can never be used again. And there is no known practical method to restore data after a single overwrite with 0s. Everything else is pure paranoia.

    Overwriting with 0s will not perfectly overwrite the tracks.

    NIST disagrees:

    On the other hand, according to the 2006 NIST Special Publication 800-88 (p. 7): "Studies have shown that most of today’s media can be effectively cleared by one overwrite" and "for ATA disk drives manufactured after 2001 (over 15 GB) the terms clearing and purging have converged."[5] An analysis by Wright et al. of recovery techniques, including magnetic force microscopy, also concludes that a single wipe is all that is required for modern drives. They point out that the long time required for multiple wipes "has created a situation where many organisations ignore the issue all together – resulting in data leaks and loss."[6]

    https://en.wikipedia.org/wiki/Data_remanence#Feasibility_of_recovering_overwritten_data

    There is some slop on the read head positioning that will normally allow enough data to be recovered that the ECC can be used to rebuild the full data set.

    This has been found not to been the case per Craig Wright, Dave Kleiman, Shyaam Sundhar R.S. in "Overwriting Hard Drive Data: The Great Wiping Controversy (doi:10.1007/978-3-540-89862-7_21 which is [6] above).

    Do you have any studies that indicate otherwise, or are you just repeating something which you once heard, at some point in time (which may or may not be valid any longer)?

    If you're really that paranoid and don't want to trust an overwrite (of which a single-pass should be sufficient), either go with thermite or an "NSA-rated" degausser:

    https://www.google.com/search?q=NSA+rated+degausser

    But seriously, a single overwrite is sufficient for us non-classified folks.