Well, at least Anthony Sanborn Jr. knew something was wrong. He was a teenage boy just convicted of murdering another juvenile on the docks of Portland, Maine, in 1989, and he knew he didn’t do it. Seemingly, and if he lived that long, he would have 70 years behind bars to think about the crime he knew he didn’t commit.

And now, decades later, evidence has come forth, and in successive doses, that points to this disturbing fact: others knew it, too. Moreover, they allegedly hid evidence that was in Sanborn’s favor, never turning it over — as legally required — to his defense team.

And then, stunningly, there was this, as revealed in a courtroom hearing last month to evaluate whether Sanborn should be freed on bail (he was) pending an upcoming post-conviction review: A juvenile female whose eyewitness testimony targeted Sanborn as the killer back in 1989 recanted her testimony entirely.

Evidence indicates she couldn’t have seen any crime being committed; she was suffering from serious and uncorrected eye problems, a fact never made known to the defense.

Sanborn’s current legal counsel says that there is plenty more exculpatory evidence that was withheld from Sanborn by state authorities both during his initial investigation, at trial and thereafter.

In fact, court documents show that a former lead detective in the case secreted important case evidence — including photographs of other possible suspects, a box cutter and knife, multiple witness statements and original police reports — in boxes tucked away in his home’s attic, constituting a clear breach of chain-of-custody imperatives and keeping critically important material shielded from the purview of Sanborn’s defense team.

Sanborn’s lawyer says that this recently revealed development will only add to arguments she has already made favoring an immediate setting aside of her client’s conviction.

That could happen soon. The judge who granted Sanborn’s bail last month stated that, given the evidence before her then, she was inclined to rule in favor of Sanborn’s conviction reversal.

She will likely be even more inclined to do so now.