1. Circumstantial evidence is not enough to convict
Convicting someone for failing to prove his innocence after accusations based solely on circumstantial evidence is a legal aberration [...]
Most legal scholars, both ancient and modern, would agree that circumstantial evidence [loosely, anything requiring inference] is typically more powerful than direct, particularly when there are independent corroborations involving the matter.
http://en.wikipedia.org/wiki/Circumstantial_evidence
For instance, forensic evidence is "circumstantial" (even the proverbial smoking gun requires an inference), while "direct" evidence (eyewitness testimony that actually saw the [alleged] crime committed) is just as prone to error/prejudice, etc. The power of circumstantial evidence is particularly when there is (or appears to be) only one logical conclusion upon its admission (in totality). It can depend on the situation, but it is more typically the responsibility of the defendant (see
Evidential burden) to propose plausible alternatives than the accuser to dream them up.
As human behaviour may manifest itself in infinite varieties of circumstances it is perilous to generalize,
but it is not every facile mouthing of some easy phrase of excuse that can amount to an explanation.
It is for a judge to decide whether there is evidence fit to be left to the jury which could be the basis of some suggested verdict...
To take this further: Finding a computing device on Ivanov's person running Houdini on the current board position would be... circumstantial. Finding a mechanism (for instance, teeth/gum electrical contacts a la Keith Taft) for passing information to said computing device would be... circumstantial. If you think this is pedantic, some "collusion" cases in bridge have concluded that while there was direct evidence that information was passed from one player to his partner (eyewitness testimony about foot tapping), there was no direct evidence that such information was actually used during play (which is a higher standard). [Yes, bridge probably does have too many lawyers who are avid players]. Maybe the issue really is that the legal term "circumstantial" is being used in a slightly inaccurate way here, and what should really be said is that "Regan's move matching statistics are not enough to convict", or "Lilov's opinions are not enough to convict", or "inexplicable board behaviour (is that an issue here?) is not enough to convict" -- I think such elucidation would help to clarify the situation.
So while I can't say that I've followed the ins-and-outs of Ivanov to say much about the case, I would say that terming the evidence [whatever it be] to be dismissible merely because it is "circumstantial" w/o proposing a plausible alternative is somewhat a futile scareword. For instance, User923005 came up with the idea that the Houdini/Ivanov move-matching in Zadat might be exaggerated due to opening preparation, which
could be plausible (I haven't analysed it, only mildly quoted Regan disputing it). As above, I think that, particularly in a quasi-formal extra-judicial process when the accusers/judges agree that the circumstantial evidence is sufficienly weighty (
prima facie as it were), it would be primarily be
Ivanov's responsibility (as the accused) to propose such alternatives, which would then be considered/discussed/rebutted further (and ultimately concluded one way or the other by the trier of fact).
again remembers me of the good old witch hunts [...] back in the middle ages they burned alive so many witches than none survived to our days.
This is historically incorrect, the Middle Ages ended in the 15th century (Gutenberg or Columbus), and the witch hunts largely came afterward. Furthermore, it is not too difficult to find self-professed witches today, even in Europe. See
http://en.wikipedia.org/wiki/Witch-hunt or
http://en.wikipedia.org/wiki/Witch_tria ... ern_period
I might point out that witch trials could have sometimes have
direct evidence (eyewitness accounts of practising witchcraft) against the accused.
If I were accused of stealing a balloon, costing one penny, I would want the same diligence and burden of proof to be applied as if I were accused of murder.
I would then expect you to defend yourself with the same diligence. As I say, I haven't followed the Ivanov proceedings closely enough to see what alternative explanations he has given (or if the Bulgarian Chess Federation has even allowed him to defend himself, for that matter).
What I mean by that is that any attack on my integrity must be completed with utter diligence and care. Of course, I imagine that I am an outlier here and others would feel differently.
My own sentiments are closer to yours. But then most modern men don't give a fig about "sacred honour" or whatever those blimey prigs centuries ago blathered on about.
Incidentally, I think that a higher diligence and burden of proof
would be applied for the [petty] theft in any
criminal proceedings (compared to civil ones), but that it would still be a somewhat lesser standard, as issues of property are not as considerable as issues of liberty (which are not as considerable as issues of life). Similarly, grand theft is a higher standard than petty theft, first degree murder (involving premediation, perhaps even malice prepense) requires more evidence than second degree, etc. From the court's standpoint, ordering (criminal) restitution is not as weighty as a temporary jail sentence, which is not as weighty as capital punishment and/or life w/o parole. But I point out that the measures here have varied over times and places (for instance, "banishment" seems no longer to be a punitive measure anywhere, or a millennium ago depriving someone of property could reduce them to such a state of destitution that e.g. public flogging/ridicule was preferred).
2. If you have an agreement to allow further scrutiny based on the circumstantial evidence and you do not follow through with that agreement, then you have violated your own word.
Again I'm not following this story too much, or relying on press accounts, but it is not clear to me that Ivanov was given "proper notification" of what exactly the tests might be (in said agreement), and perhaps he decided not to go through with the testing because of that. On the positive side for him, I don't think anyone could say that Ivanov is personally mounting a "defense via the press" in any sense, but I do think he should strive to resolve the issues either with the BCF or FIDE (both paragons of integrity -- NOT!) if he thinks he is being unfairly treated.