NJ cop who killed ex-girlfriend, beau threatened to kill himself months before murder-suicide: victim’s sisters

The beloved veterinarian murdered by her New Jersey cop ex-boyfriend reached out to one of his state police colleagues when he threatened to kill himself just months before the tragic murder-suicide, the woman’s sisters said Tuesday.  

Lauren Semanchik’s contact with the female colleague possibly led New Jersey State Police Lt. Ricardo Santos to undergo a mental evaluation at his job in May, sisters Allison and Deanna Semanchik told The Post.

But Semanchik’s plea for help also fueled his erratic rage, his sisters alleged, which ended when he fatally shot his ex-girlfriend and her new beau, Tyler Webb, Friday night before turning the gun on himself.

The slain couple was found by Semanchik’s father the next day, with Santos’ body discovered about 50 miles away in his car.

After the pair broke up in September, Santos began a relentless campaign of harassment against Semanchik, 33, that eventually convinced her to seek help.

“He has been threatening to kill himself and Lauren being herself, was concerned for his well-being despite everything he had done to her already,” younger sister Allison Semanchik, 28, said in an interview.

“She didn’t want that to happen and didn’t want that on her conscience so she only knew one person that also knew him and contacted her, and from what I understood and what I was told by my sister that got him put under mental evaluation.”

Allison and her other grieving sister, Deanna, 36, stressed they don’t know if he actually underwent a mental checkup or faced other action — but they both slammed state police for not spotting Santos’ mental health problems and helping him.

“A little bit of due diligence for their people, the people that they claimed to support and that we’re supposed to rely on to protect us,” Allison said, adding, “It should be more of a requirement that they actually be checked up on.”

State police and the New Jersey Attorney General’s Office did not reply to emails seeking comment on whether Santos underwent a mental evaluation.

The attorney general’s office said in an earlier statement it was withholding comment until prosecutors in Hunterdon County wrap up their probe of the unthinkable crime.

Lauren’s sisters said that after she reached out to the female colleague, Santos became more unhinged and accused her of trying to ruin his career, which included providing security for Gov. Phil Murphy and other dignitaries.

Semanchik thought he had keyed her car outside her job the following day, which led her to file a police report in Long Valley. Santos was notified that he was a suspect in the vandalism, according to Deanna Semanchik.

She later went to the police station in Franklin Township, where she lived, in hopes of filing a restraining order, but was told no one was able to help at that time and to call a number, Deanna said.

Semanchik called and left a message that was never returned, her sibling said.

Franklin police also did not respond to a request for comment.

In New Jersey, a court ultimately decides whether a restraining order will be granted, but police departments can help with the process, according to Lauren Van Metre, the executive director of Safe in Hunterdon — a center that served domestic violence survivors.

Allison said Semanchik treaded carefully about whether to lodge a restraining order because Santos was a police officer, while Deanna added, “She just hoped that he would go away.”