PLAINVILLE — Lawyers for Michelle Carter have been granted more time to appeal her manslaughter conviction to the U.S. Supreme Court.
Supreme Court Justice Stephen Breyer this week gave the lawyers until July 8 to file, according to court records.
Carter, 22, of Plainville, is serving a 15-month jail term for the death of her boyfriend, 18-year-old Conrad Roy III of Mattapoisett, in 2014. The state Supreme Judicial Court unanimously upheld her 2017 conviction in February.
Carter, then 17, urged Roy to kill himself in a series of text messages and phone calls from her home.
Roy died after breathing in toxic fumes from a water pump inside his pickup truck while parked in a Fairhaven parking lot.
Carter is represented by Nancy Gertner, a Harvard law professor, high profile defense lawyer and former U.S. District Court judge, as well as Boston lawyers Daniel Marx and William Fick.
In a document filed to request an extension, they wrote that the state Supreme Judicial Court was the first to have affirmed a conviction for a defendant who — with words alone — advised, encouraged or coerced another person to commit suicide, noting that Carter neither provided the means of death or physically participated.
The lawyers argued the state’s high court created a conflict with at least three other state supreme courts about the application of the First Amendment in such circumstances. The court, they said, also disregarded U.S. Supreme Court precedents regarding due process guarantees.
The lawyers argued that the ruling failed to draw clear lines, which the Constitution requires, about who could be prosecuted for encouraging or assisting someone who commits suicide.
They said the state Supreme Judicial Court ruling left up to prosecutors and judges “the difficult task of differentiating on an ad hoc and subjective basis between such cases.”
“Its dubious assumption that prosecutors will act responsibly in charging involuntary manslaughter in future suicide cases undermines the constitutional protections, which this court has clearly established and consistently maintained against arbitrary enforcement of criminal laws,” they wrote.
In seeking more time, the lawyers cited their pressing work for other clients, including indigent ones in court-appointed cases.
Among them are plaintiffs in an ongoing federal civil rights action seeking the return of fees and fines paid and property forfeited in wrongful convictions due to misconduct in the state drug laboratory.
The state Supreme Judicial Court dismissed thousands of cases after an investigation revealed a state chemist tampered with drug evidence sent to the lab to be tested.