When ‘Fixing It Later’ Fails: The Hard Truth of Ineffective Assistance Claims and the Lessons of Commonwealth v. Mosso
In Commonwealth v. Gary E. Mosso, the SJC did something that looks, on paper, like a win for defendants. The court formally recognized that trial counsel can be constitutionally ineffective for ignoring a client’s reasonable request to pursue a plea, even when the Commonwealth has never made a formal offer. But then, in the next breath, the court denied Mosso’s motion for a new trial.
That tension is exactly why this case matters. It’s a reminder that:
Winning a new trial on ineffective assistance is brutally hard, especially decades later; and
If you’re going to litigate one, you need a meticulous record built under the Saferian framework, or you are going to lose on “speculation.”
This case quietly tells defendants—and lawyers—the same uncomfortable truth: you cannot count on fixing bad lawyering later. You need effective counsel now.
Factual Background
Mosso and a codefendant were tried together in 1984 for the beating death of Anthony Tamburro. A Worcester County jury convicted both of murder in the first degree by extreme atrocity or cruelty on a joint venture theory. Each man received the mandatory sentence: life without the possibility of parole. The SJC affirmed both convictions on direct review under G. L. c. 278, § 33E.
Decades later, the codefendant filed a motion for a new trial, claiming ineffective assistance in the plea negotiation stage. His basic story:
He told his lawyer to “get a deal” before trial.
Counsel allegedly told him the prosecutor wouldn’t take manslaughter.
He claimed he was never properly advised about the gradations of homicide and their sentencing consequences.
He said that if he’d understood the difference, he would have pushed to plead to murder in the second degree before trial.
He also claimed that two weeks into trial, he told his lawyer to “make happen” a plea to second degree; counsel tried, but the prosecutor said no at that point.
The motion judge (not the trial judge) held an evidentiary hearing, heard from the trial prosecutor, an expert, and the codefendant, and essentially found:
The prosecutor would never have accepted manslaughter.
A plea to second degree was conceivable, but only if both defendants took it.
The codefendant’s testimony about not understanding homicide gradations wasn’t credible.
By the time the codefendant was finally willing to plead to second degree (mid-trial), the family had already been put through testimony and the prosecutor was no longer interested in resolving.
The judge called the motion “speculation about what could have happened” and denied it.
Mosso then filed his own motion for a new trial, also built on the plea-negotiation stage, but with a slightly different theory. He claimed:
Unlike his codefendant, he did understand the difference between first and second degree murder and their sentencing consequences.
He repeatedly told his lawyer to seek a deal—to explore “pleading guilty to something less than murder in the first degree.”
He only learned in 2016 that (1) counsel had not followed through, and (2) the prosecutor might have been open to a global plea to second degree if both defendants agreed.
By the time Mosso filed, his trial lawyer had died. There were no notes from counsel, no letters, no contemporaneous record. The same motion judge held another evidentiary hearing, heard from the prosecutor, an expert, and Mosso, and folded in the previous record from the codefendant’s motion.
The judge credited the prosecutor, disbelieved parts of Mosso’s account, and concluded that Mosso hadn’t carried his burden. The SJC took the case on leave to appeal and affirmed.
2. What the SJC actually held: yes, this can be ineffective assistance—but you still lose
The SJC’s legal holding is important and, on its face, defendant-friendly:
A defendant does have a cognizable ineffective assistance claim where trial counsel ignores a reasonable client request to explore a plea, even if the Commonwealth has made no formal plea offer.
Under art. 12 (interpreted coextensively here with the Sixth Amendment), counsel’s performance can fall “measurably below” Saferian if an ordinary fallible lawyer, in those circumstances, would have pursued the requested plea conversations. Massachusetts Government
That’s the first Saferian prong: deficient performance.
But then comes the second prong: prejudice. And this is where the SJC makes clear just how steep the hill really is in a motion for new trial based on plea-stage ineffective assistance.
To show prejudice when counsel fails to pursue a client’s reasonable plea request, the defendant must show a reasonable probability that:
The prosecutor would have entertained and accepted the plea the defendant wanted to pursue;
The plea would have been presented to and accepted by the judge; and
The loss of that plea opportunity led to a trial producing either a more serious conviction or a harsher sentence than the plea would have carried. Massachusetts Government
That’s a three-link chain, and you have to solidly build each link with something more than conjecture.
In Mosso’s case, the SJC was willing to assume the first prong of Saferian in his favor:
Assume he really did instruct counsel to seek a plea.
Assume that plea (second degree murder) was objectively reasonable.
Assume counsel simply never raised it with the prosecutor.
Even with all of that assumed—deficiency essentially conceded for argument’s sake—Mosso still loses, because he can’t make the prejudice showing.
Why? Because the prosecutor credibly testified that:
He would have considered a global plea to second degree for both defendants;
He would not have accepted a stand-alone plea from Mosso;
The value of Mosso as a witness against the codefendant was limited by his inconsistent statements; and
The victim’s family had already been put through the emotional cost of trial by the time any second-degree talk from the codefendant became real.
Critically, the codefendant didn’t seriously come to the table on second degree until the second week of trial. By then, the prosecutor’s window for a global disposition had closed. On this record, the SJC agreed with the motion judge: there was never a “realistic probability” that Mosso alone could have pled to murder in the second degree.
No realistic probability of an actual plea = no prejudice = no new trial.
3. The Saferian frame: why making a record matters
Massachusetts uses the Saferian standard for ineffective assistance under art. 12: the defendant must show that:
Counsel’s performance fell “measurably below that which might be expected from an ordinary fallible lawyer,” and
That failing “likely deprived the defendant of an otherwise available, substantial ground of defence.”
In the plea context, that “substantial ground of defense” is often not a trial defense at all—it’s the opportunity to resolve the case on less damaging terms: fewer charges, lesser degrees, or a substantially lower sentence.
Mosso is a good illustration of how Saferian actually plays out in a motion for new trial, especially many years after the fact:
The deficiency prong is sometimes the easier one to satisfy. Modern professional norms—CPCS guidelines, ABA standards, SJC cases like Marinho, Mahar, Camacho—all say that competent counsel must explore reasonable plea options and communicate client preference. Ignoring a reasonable “please seek a deal” request looks bad.
But prejudice is where new-trial motions go to die. Judges are deeply wary of “what might have been” narratives, especially when they depend heavily on a defendant’s memory, decades later, and trial counsel is dead or unavailable.
That’s why the SJC emphasizes that speculation is not enough. To win, you need concrete evidence about:
The prosecutor’s actual willingness to resolve the case a certain way at a certain time;
The office’s policies and culture at that point in history;
The likely reaction of the victim’s family;
The trial judge’s practices;
The defendant’s actual willingness and understanding at the time, not in hindsight.
In Mosso’s case, the prosecutor gave detailed, credible testimony about all of that. Mosso could not produce anything comparable from his side—no letter to counsel, no notes, no affidavit from trial counsel, no contemporaneous record of his “get a deal” requests. The motion judge credited the prosecutor, discounted key pieces of Mosso’s story, and the SJC deferred.
That is the real lesson: if you cannot build a detailed factual record under Saferian, you are not going to win.
4. Why this matters in the real world: you can’t assume you’ll fix bad lawyering later
From a defendant’s point of view, there’s a dangerous myth:
“If my lawyer screws it up, we’ll just claim ineffective assistance later and get a new trial.”
Mosso is a cold answer to that myth.
Even when the SJC is willing to say, “Yes, this sort of failure can be ineffective,” it still demands a highly specific factual showing about what the prosecutor, the judge, and the defendant would have done in real time, not in hindsight. When the trial lawyer is gone and the only thing left is the defendant’s recollection, you are fighting uphill.
In practical terms, that means:
You cannot bank on an IAC motion as a safety net.
The pleas you don’t explore, the discussions you don’t have, the advice you don’t document—they are very hard to reconstruct years later.
“He should have gotten me a better deal” sounds compelling in conversation; it sounds speculative in a motion.
The SJC’s message is not “you can never win these cases.” They’ve granted new trials in the plea context before. But Mosso shows how narrow the path really is.
5. After conviction, you must prove more than bad lawyering—you must prove it changed the result
Under the Saferian standard, a defendant filing a motion for new trial has to prove two things:
Your lawyer’s performance was measurably below what an ordinary lawyer should have done, and
Because of that mistake, the outcome of your case was probably worse.
Courts are strict about both prongs. A motion for new trial will be denied if you prove the first but not the second.
In the plea-bargaining context—like in Mosso—you must show a reasonable probability that:
The prosecutor would have accepted the plea you say you wanted;
The judge would have approved it; and
You would have received a less serious conviction or a shorter sentence.
If you can’t prove all three, the motion fails.
This is why convictions from decades ago are so hard to unwind. You’re trying to reconstruct conversations, negotiations, and decisions long after memories have faded and lawyers may have passed away.
a. Judges will not fill in the gaps—you must bring real evidence, not speculation
The biggest problem defendants face is that motions for new trial often depend on assumptions:
“My lawyer should have gotten me a deal.”
“The prosecutor would have taken something less.”
“The judge probably would have agreed.”
Courts call these kinds of arguments speculative, and speculation is not enough to win.
To succeed, you must bring concrete proof, such as:
Testimony from the prosecutor about whether a plea was possible,
Expert testimony about professional norms,
Written guidelines (like CPCS manuals),
Evidence of the DA’s office practices at the time,
Anything in the file showing what discussions actually took place.
If the record is thin, or if nobody documented conversations, the court will almost always rule against you—because you have not shown the result would have been different.
b. The takeaway for defendants: motions for new trial require strong, detailed, well-supported arguments
If you’ve already been convicted and believe your lawyer failed you, the question becomes:
Can you prove—not guess—that the mistake cost you a better outcome?
That’s the standard you have to meet. It’s demanding, and Mosso makes clear that many cases fail because the evidence simply isn’t there.
That’s why motions for new trial require:
A thorough investigation,
A careful reconstruction of what happened and what should have happened,
Expert input where appropriate, and
A legal strategy built entirely around satisfying the Saferian standard.
It’s not enough to say your lawyer was ineffective. You must prove it, and then prove the prejudice.
For defendants and families: choosing counsel up front matters more than you think
From the outside, it can feel like lawyers are interchangeable. They’re not.
In a life case, you need someone who understands how plea negotiations intersect with trial strategy, and who will not let a reasonable plea opportunity drift away.
You need someone who knows how to protect you now and preserve your rights for later—by advising you clearly, documenting advice, and making appropriate records.
And you need that person before you are sentenced, not twenty or thirty years later.
One theme of Mosso is that it’s possible to have a constitutional violation in the plea stage—and still be stuck with a first-degree murder conviction and life without parole—because the proof of “what would have happened” simply isn’t there.
That is a hard outcome to read. But for people facing serious charges, it carries a simple, urgent message:
Don’t count on a motion for new trial to rescue you from ineffective lawyering.
Your best—and often only—chance is to have effective counsel in the first place, and to pursue plea negotiations, if the client wishes it.
If you or someone you care about is charged with a serious offense and you’re worried that plea decisions, advice, or negotiations are not being handled carefully, that’s not something to ignore or “save for later.” That’s the moment to get a second opinion and make sure your rights, and your record, are being protected right now.
If you’re standing at the beginning of a serious case, the safest path is to make sure you have effective counsel from the start. The stakes in major felonies leave no margin for error, and once the record is closed, courts hold you to it. At Benzaken, Sheehan & Wood, LLP, we take that responsibility seriously—whether we’re guiding clients through plea negotiations, preparing for trial, or preserving every issue for appeal. And if you or a family member believes an earlier lawyer’s mistakes have damaged a case, we also handle post-conviction litigation and motions for new trial with the rigor these claims demand. To speak with an experienced defense and post-conviction attorney, call (508) 897-0001. Your best chance begins with choosing the right counsel.