It's been nearly a year since lawyer was slain and family wants closure

ASPEN BIRNBAUM was alone at an out-of-town college last Feb. 11 when a heartless gunman far away turned her world upside down.

She was told by phone that her father, lawyer Eric Birnbaum, had been gunned down in Holland, Bucks County, and would not survive the injury, Aspen told the Daily News yesterday.

"I dropped to the ground. I didn't really believe it" and everything became a blur, said Aspen, 19.

"I couldn't believe that somebody could take him away" - she said, then through sobs - "that everything was going to go on without him."

Aspen and her older sister, Sloane, 21, lost a part of themselves on that unusually warm, sunny February day when their "selfless" dad was shot once in the back of the head by a cold-blooded killer who still eludes authorities.

Gone were daily text messages and frequent phone calls from their father wondering about the girls' safety and health. That role has been taken up by their mother and his family: the girls' aunt, grandparents and their "uncle," Terry D. Goldberg, who is actually their godfather and father's lifelong best friend and law partner.

The unknown assailant killed Birnbaum in the parking lot in front of Goldberg's law offices, where Birnbaum worked.

Birnbaum, a personal-injury lawyer, was talking with a co-worker by his car when the gunman, described by witnesses as a white male, between 25 and 45 years of age, wearing a knit cap and dark sunglasses, appeared out of nowhere and fatally shot him.

Now, nearly a year later, the Birnbaum family wants closure.

"My nieces have the right to know what happened to their dad," said Eric Birnbaum's sister, Dona Birnbaum. "My family needs closure . . . this is such a senseless crime."

The Northampton Police Department and the Bucks County District Attorney's Office would like nothing better than to solve the case as the anniversary of Birnbaum's slaying approaches. Authorities insist that the case is a top priority and said that more than 100 people have been interviewed.

"This is on the front burner of the District Attorney's Office and the Northampton Police Department and we are pulling out every stop in order to solve it," said David Zellis, first assistant district attorney. "We're not going to stop working our tails off until we crack the case."

Investigators said they'll find the killer. "There's no frustration that's developing by the investigators on this case," said Sgt. Det. Bill Klein. "We're all veterans and we know that some cases take time to solve. If anyone thinks this has been put to a back burner, they are wrong."

It's certainly on the minds of associates and friends, who recently pulled together more money to double the reward to $20,500, the Citizen's Crime Commission of Delaware Valley confirmed yesterday.

The America's Most Wanted Web tip line received an anonymous call in May that Detective Charles Pinkerton called "very significant."

"We'd like that person who made that tip to contact us," said Pinkerton, who has been on the case since Day One. He declined to give specifics about what the caller said, but stressed "we want to speak to that person who made the tip."

The victim's daughters have no idea why anyone would want their father dead. He was well-liked by legal colleagues, clients and insurance-company representatives, according to Northampton police and Goldberg.

"He would never hurt a fly," said Aspen, a psychology major looking to study law.

Sloane, also in college, and Aspen miss the close relationship they had with their father, who'd do anything for his kids, even "girlie things" with them, Sloane said yesterday.

After their parents divorced when they were young, Birnbaum was both "dad and mom," she said. "He'd go shopping with us, he'd braid our hair, he'd cook for us."

Unlike most of their friends' dads, Birnbaum had no problem sitting down and watching the girls' favorite teenybopper TV program with them, Sloane said.

"He was the most selfless person I knew."

Anyone with information is asked to call Northampton police at 215-322-6111.