David and Linda Kubert of Dover, who both suffered serious leg injuries as a result of the 2009 crash in Mine Hill Township, sued Best and settled the case last year.
While the appellate court found that the Kuberts - who also sued the girl after learning that she and Best had exchanged 62 texts the day of the crash - didn't present enough evidence for the claim, it said other third-party texters could be held liable in accidents, depending on what they knew about the driver receiving the messages.
"We do not hold that someone who texts to a person driving is liable for that person's negligent actions," the opinion said.
But "when a texter knows or has special reason to know that the intended recipient is driving and is likely to read the text message while driving," the opinion said, "the texter has a duty to users of the public roads to refrain from sending the driver a text at that time."
In deciding that a texter not in the car could face responsibility for an accident, the court has set precedent, said Stephen "Skippy" Weinstein, a Morristown personal injury lawyer who represented the Kuberts.
Weinstein had argued that the girl who texted Best was "electronically present" in the car.
"This is a very powerful written opinion that steps out of the box and creates very comfortably a cause of action that had never been created in the United States before," he said.
Under the standard described in the opinion, a texter who receives a response from a person he knows is driving and continues the conversation could be held liable, Weinstein said.
Of the three appellate judges who heard the case, one issued a separate opinion, agreeing with the majority that there wasn't enough evidence to find that the girl who texted Best shared blame. She sent Best one message right before the accident, according to phone records, which didn't reveal its content.
But Judge Marianne Espinosa argued that the law already provides a "sufficient measure for assessing the liability" of someone who texts a driver.
"I see no reason to establish a new standard for such conduct, particularly when the record before us does not support the imposition of liability upon the remote texter," Espinosa said in the opinion.
It's not clear whether the new standard outlined in the majority opinion will be upheld by other state appellate divisions or the state Supreme Court, said Jenny Carroll, an associate professor of law at Seton Hall University.
While the appellate judges said it's not enough for a texter to know a recipient is driving - he must know the driver will read the message - the limits of that liability may expand as texting becomes increasingly prevalent, Carroll said.
"At some point, is there an assumption that it would not be unreasonable to anticipate if I text you, you would read it immediately?" she said. "There's lots of open questions this raises."
New Jersey bans both texting and handheld cellphone use while driving. Last year, lawmakers passed a bill allowing prison time to be imposed for drivers who illegally use a cellphone and cause an injury or death.
A bill introduced this year would give the police the right to confiscate cell phones at car accident scenes, a measure its sponsor has said is aimed at changing driver behavior.
Contact Maddie Hanna at 609-989-8990 or email@example.com, or follow on Twitter @maddiehanna