A series of recent incidents at the Upstairs Downstairs bar at Neponset Circle could cost the establishment its 2 a.m. closing time.

The Boston Licensing Board decides Thursday what to do about incidents involving brawling women in December, January and February that required every available cruiser in Dorchester to respond. In one incident, some patrons took advantage of the commotion to jump behind the bar and empty the cash register and haul off several bottles of liquor. In another, a Boston police officer on detail in the bar heard bottles smashing behind him - at which point a bartender jumped on the bar, turned on the lights and told people to leave.

"You saw no punches thrown did you?" bar attorney Robert Quinn asked the officer. "No, only bottles," he replied.

"A radio call goes out which requires all the units in C-11 to go down and respond to the Quincy line and deprives the rest of Dorchester of police protection," Pokaski said. "Why should this board put up with that? We can't allow that to happen. It's gotten out of control. ... It's not going to continue as it is. It just isn't."

The bar says it's attempting to stop problems by cutting the number of people allowed upstairs - where the bar plays hip hop, rather than the Sinatra-style crooning downstairs. Although the bar can legally allow up to 137 patrons there, it is now cutting off admittance after just 80 people walk upstairs. It's also stopped serving drinks in glass upstairs.

The bar also hires two detail officers on weekends, but Sgt. Thomas Brennan of District C-11 said Upstairs Downstairs is going to have problems finding cops in coming months, partly because of summer vacations, but also because a number of officers now refuse to take a job at a place where they have to worry about flying bottles.

Quinn asked the board to give these measures a chance before considering cutting back the bar's hours or taking other measures.