May 21--Pick a fight in some Long Island nightclubs and it won't be a brawny bouncer banning your return.

It will be a cyberbouncer - lifeless and smaller than its human counterpart - that will help keep troublemakers at bay.

The BioBouncer, a high-tech computer and camera that analyzes club patrons' faces and stores the images, debuts worldwide Memorial Day in a pilot program at four Island Park nightclubs.

Queens-based JAD Communications and Security developed BioBouncer, a sleek metal pole topped with a light and digital camera that feeds data to an on-site computer. Company president Jeff Dussich said the camera would help curb club violence by barring troublemakers whose pictures had been taken previously by the device and saved in its database.

"We are not just looking at a way to clean up one or two bars, but also a community," said Dussich, a 24-year-old Manhasset native.

Its arrival next weekend has raised concern about whether the device will violate clubgoers' rights by taking large numbers of photographs of law-abiding patrons. Civil rights groups fear BioBouncer could further erode what they see as shrinking privacy rights in a society where surveillance cameras sit atop traffic lights and many public buildings.

Questionable, but legal

The groups also say they are concerned law enforcement agencies could pressure clubs that use the machine to hand over the images as part of criminal investigations, and they add that someone barred from one club could be barred from other clubs that also use BioBouncer, a practice experts say is legal.

"It's not illegal, but it's certainly going to lead to a lot of errors and mistakes and people getting kicked out of clubs who haven't done anything wrong," said Chris Calabrese, counsel for the American Civil Liberties Union's technology and liberty program. "I think [club owners] are going to find it as a bad business model."

Others say critics are making too much of a photograph taken at a private business used to identify problem customers.

"People are taking biometrics and negatively comparing it to worries of Big Brother," said Robert Smith, a San Diego detective and nightclub security expert. "You're not looking for terrorists, you are not looking for wanted criminals, you are only looking for guys who are making trouble."

Dussich said law enforcement agencies investigating crimes would not have access to the pictures. However, law enforcement officials believe BioBouncer may do little for them anyway.