Commonwealth v. Lydon, 477 Mass. 1013

David Lydon was serving a six‑month committed sentence in the house of correction (Roxbury charges) after stipulating to a probation violation.
While serving that Roxbury sentence, Lydon pleaded guilty to unrelated Superior Court robbery charges (Dorchester charges).
At Dorchester sentencing the judge imposed a committed State prison sentence "forthwith and notwithstanding" the house of correction sentence, and credited 36 days of pretrial detention against the Dorchester sentence.
Lydon requested additional credit for the 132 days he had already served on the Roxbury house of correction sentence; the judge denied the request.
Lydon appealed, arguing not for an entitlement to credit as of right but that the sentencing judge had discretion to (a) award direct jail credit or (b) make the later State prison sentence concurrent nunc pro tunc to the start of the house of correction sentence.
The Supreme Judicial Court held that direct credit was not available on this basis but that the judge had discretion to consider imposing the later State prison sentence nunc pro tunc to the commencement of the house of correction sentence; the case was remanded for reconsideration.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether a sentencing judge has discretion to award direct jail credit on a sentence for time served while serving an unrelated sentence	Commonwealth: direct credit is not warranted here	Lydon: Ridge permits discretionary granting of jail credit in such circumstances	No — Ridge does not support discretionary direct credit for time served on an unrelated sentence
Whether a sentencing judge may, in the exercise of discretion, impose a later sentence concurrent nunc pro tunc to the start of an earlier unrelated sentence to effectively afford credit	Commonwealth: judge correctly denied additional credit	Lydon: judge could instead impose the State prison sentence nunc pro tunc to the house of correction start date to achieve the same result	Yes — judge has discretion to order a later sentence to commence nunc pro tunc to the earlier sentence; remand for exercise of that discretion

Commonwealth v. Ridge, 470 Mass. 1024 (2015) (discusses when sentencing judges may grant or deny jail credit requests)
Ledbetter v. Commonwealth, 456 Mass. 1007 (2010) (distinguishes credit for time served on an unrelated sentence)
Commonwealth v. Barton, 74 Mass. App. Ct. 912 (2009) (recognizes possibility of imposing later sentences nunc pro tunc to align multiple sentences)
Dale v. Commissioner of Correction, 17 Mass. App. Ct. 247 (1983) (effect of "forthwith and notwithstanding" sentencing language terminating prior house of correction sentence)
Commonwealth v. Ruiz, 400 Mass. 214 (1987) (distinguishes knowing exercise of discretion from belief that decision is compelled)