The Boston Licensing Board decides tomorrow whether to let Insomnia Cookies open a storefront on Bromfield Street from which it would deliver warm cookies to downtown residents and students up to 3 a.m.

A representative from the mayor's office agreed to support the proposal after the chain, which has similar outlets in Kenmore and Harvard squares, agreed to add cameras and lighting to try to ward off and catch the sort of ne'er-do-wells one might expect to congregate on a downtown side street so deep into the night. At a licensing hearing this morning, chain officials added they would be agreeable to nighttime removal of the four to six high-top seats it plans to have at a window counter during the day.

But Doug Meyer of the Downtown Boston Business Improvement District, which represents downtown businesses - and runs litter-removal and "ambasssador" programs - said "we just don't feel particularly comfortable" with a 3 a.m. closing time and urged the board to step it back to 2 a.m.

Under its proposal, Insomnia would take its last orders at 2:45 a.m., to allow for a buffer to get all those last-minute cookies delivered by 3.