Midland Park Ambulance took Jeffer, 69, to Hackensack University Medical Center from his Post Street home after he apparently shot himself in the abdomen, sources with direct knowledge of the incident told Daily Voice.
He was conscious and alert at the time, witnesses reported.
Midland Park Police Chief Michael Powderly said he couldn't release the identity of the victim.
However, he told Daily Voice that the man was expected to survive and that the weapon was legally owned.
Wyckoff police joined their Midland Park colleagues at the scene.
Jeffer, a retired Municipal Court judge and former Midland Park firefighter, owns Wortendyke Arms, known as the seller of "New Jersey's Guns For the Good Guys."
Next month marks 44 years that he's been an attorney.
Daily Voice Deputy Managing Editor Rebecca K. Abma contributed to this story.
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