First of all, it’s just a hypothetical to illustrate the pitfalls of assuming there is an easy answer to “what do you do if you are erroneously accused of murder and the evidence appears damning?”
Second, ignoring what I just said and treating the hypothetical as something really worth in depth analysis, what makes you think your defense attorney holds that kind of negotiating power? What makes you think the prosecutor will be motivated to deal at all? After all, we’re talking an ATM camera here and it was dark out. Sure, you say it’s you, but all we can really discern is that it’s someone of your general size and shape.
You might think, and I would agree, that surely the prosecutor would want to know if he’s got the wrong man in custody, and wouldn’t least investigate your alibi further and in good faith, employing state resources to fully investigate, but…
Yeah. Stories of the genuinely innocent but wrongly convicted are replete with examples of people where an unbiased view of new evidence makes it clear the prosecutor really did put the wrong person on trial, but where even after the person has been exonerated and released the prosecutor insists the evidence was and is air tight and the appeals court ought to be ashamed of itself.
It’s really all just a way of saying… sometimes prosecutors fuck up, in a subset of caes prosecutors will double down long after the weight of evidence makes clear they fucked up, that some defendants at least, and hopefully all defense attorneys know this, and that merely keeping a close-hold on an alibi for as long as possible (hoping to keep the prosecutor flat footed so they will get tripped up in front of the jury and fumble the case) makes sense from a certain point of view.
Prosecutors developing tunnel vision is in fact but one of many incentives for even an innocent person to refuse to cooperate with an investigation. For instance, did you know that if you make a statement to someone else, and later end up as a defendant, and you then try and bring the person in to repeat what you said, it will likely be excluded as hearsay, but that if the prosecution does the same it will be admitted as a statement by a party opponent? Which means that all the prior statements you made that, if true, would tend to undermine the prosecution’s case will be inadmissible to help you by default, while anything you might have said that would tend to incriminate you, such as if you misspoke about the time when you were selling drugs in front of the ATM because under pressure you misremembered, will be admissible as evidence against you, that you fabricated the ATM story? Suppose, for example, you said you were there (thinking back many months) from midnight to 5AM, when in fact the dealer appears on camera from 1AM to 6AM. A perfectly plausible alternative story of the ATM footage, then, is that, sure, someone was dealing there—we can all see that with our own eyes—but you were probably just one of the customers, and you came by before or after the murder to get high, and you only latched onto this “alibi” later out of desperation. After all, there’s mounds of other evidence against you and doesn’t that really seem more plausible to you, oh fair and impartial jury? I mean, we just knowing this guy is lying because he didn’t immediately confess to a number of other felonies in response to being arrested for murder, and when he finally did talk details of his alibi were inconsistent with the ATM footage…