You pick something, any aspect of ID as proposed by Michael Behe, and show how it could be falsified by an observation.
As to methods, we can potentially gain an idea of what examples of ID might look like, as we've got examples of human ID (e.g., genetic engineering) where we know the answers up front. If it is possible to formulate set of tests that reliably identify human-caused changes, then at least in theory we could attempt to test other phenomena using the same techniques. A positive result would be very interesting. A negative result would be interesting, too.
When someone has actually done that work come back and report. Problem is identifying human design is relatively easy. ID'ers believe that the designer is the God of the bible, in which case everything in the universe is designed in which case your design filter, if correctly designed should show that. Hardly a useful conclusion. How would you know that it was working?
By the same token, I could ask the same question of you: what conceivable observation could show Evolution (as an over-arching explanation) to be false? For example, if the fossil record were to show sudden sharp changes, rather than a slow and steady progression of accumulated changes, would the Theory of Evolution be falsified? We know the answer to that is "no." The response was, rather, to adjust the theory to match the observations.
I think you've asked me that question before, and my response was that a DNA retrovirus in both gorillas and humans but not chimps would neatly falsify ToE. Likewise any chimera that didn't fit into the tree of life. Your assumption about sudden change in the fossil record is false. The changes described by creationists as "sudden" take tens of millions of years. No dogs giving birth to cats, I'm afraid.
Note also that there are some on these threads whose arguments against ID include a claim that one could not recognize ID even if it did occur. Think about that for a moment: what does such a claim imply for evolutionary theory?
I've no idea. Evolution is perfectly easy to recognise and millions of data-points that could potentially have falsified it have instead supported it. To the extent that even the leading ID scientific luminaries acknowledge that evolution is true, and that the Designer has not interfered (as far as they can see) for hundreds of millions of years.
Anyway, lets see that test for ID, a real-world observation that would show Behe to be wrong, for example.
Behe has suggested that the flagellum would be a great test. Given advances in nanotechnology and microbiology, one can at least plot out a path to constructing them, probably within the next 20-50 years. The ID hypothesis could be falsified if one were to construct a test whereby we could observe flagella developing through a process of evolution. Behe's claim that ID is "necessary" for the development of flagella would be invalidated.
Which of course raises a corollary question: the current hypothesis is that flagella evolved. Has anybody ever tested it?
ID'ers believe that the designer is the God of the bible, in which case everything in the universe is designed in which case your design filter, if correctly designed should show that.
Nope. You've overstepped your assumptions here. It's true that many religious people are at least open to the possibility that God did it all (and many even demand it). From a strictly scientific perspective, however, it is not necessary to invoke God in order to make an ID claim (bioengineering is an example of this). Nor is it necessary to assume that ID and Evolution are mutually exclusive processes.
Your assumption about sudden change in the fossil record is false. The changes described by creationists as "sudden" take tens of millions of years.
It's not "my assumption." Leaving aside the merits of the theory itself, the folks who thought up "punctuated equilibrium" were responding to a perceived problem with the ToE, as it shows up in the fossil record; namely, how to account for a fossil record that showed long periods of stasis, followed by relatively sudden sharp changes. They were concerned about this -- it didn't match the "slow and gradual" hypothesis that even now pervades the popular view of Evolution.
and my response was that a DNA retrovirus in both gorillas and humans but not chimps would neatly falsify ToE.
It wouldn't "falsify" the ToE, for which there is other supporting evidence. It would do no more than to disrupt the currently held belief about how humans and apes evolved, and would be announced in headline fashion along the lines of "Scientists forced to rethink human ancestry." It might also suggest that there was a mechanism other than evolution involved in that particular characteristic -- but the question in that case would be: what other mechanisms would you allow to be hypothesized?