The wife and daughters of the accused arsonist at the center of the New Jersey mansion murder mystery think he’s a hero — and they hope to testify on his behalf , his lawyer said.

Paul Caneiro, 51, is charged with torching his Ocean Township home in the predawn hours of Tuesday.

Seven hours later, his brother and business partner, Keith, was found shot dead on the lawn of his burning $1.5 million mansion in Colts Neck, 10 miles away. The bodies of Keith’s wife, Jennifer, and their son, James, 11, and daughter, Sophia, 8, were inside, all of them homicide victims, officials said.

But while Caneiro has been charged with dousing his home with gasoline and setting it alight — and a forensic investigation continues at both charred properties, so more charges could be pending — his wife and two adult daughters believe he’s innocent and that he in fact saved their lives, his lawyer said.

“In the criminal complaint, his family is listed as the intended victims. But they firmly believe that he actually saved them,” defense lawyer Rob Honecker told Patch.

“He was the one who woke them up and got them out of the house” as the smoke detectors went off, he said.

The wife, Susan, wants to testify on Caneiro’s behalf, and she and the daughters, who are both in their 20s, are hoping to visit him in Monmouth County jail this weekend, Honecker said.

Caneiro’s next court appearance is a bail hearing set for 9 a.m. Wednesday.

Asked if Caneiro was also the victim of the arson at his home, Honecker told the outlet: “I don’t know what happened or what caused the fire. All I know is that Paul Caneiro had nothing to do with it.”

Caneiro was “devastated” to learn that his brother, and his brother’s family, had died in Colts Neck, the lawyer said.

Caneiro was at the Ocean Township police headquarters when officials gave him the news, the lawyer said.

“They all were, his wife, his whole family there with him when they heard that news. Crying, you name it.”

The two Caneiro brothers, who are originally from Brooklyn, are business partners and got along just fine, the lawyer insisted.

Their Asbury Park-based tech company, Square One, installed computer networks for Citibank two decades ago. The brothers also ran an extermination company.

Neighbors said Paul owned several Porsches. Keith had a temper, a neighbor claimed.

“I can make all your animals disappear,” an organic farmer who lives next door alleged Keith threatened five years ago, after a dispute over a barking dog.