Part of Mayor Vincent Gray's 2012 budget calls for expanding the city's sales tax base to include "live performances".
Arts groups like Cultural Tourism D.C. and the Helen Hayes Awards are against the proposed Budget Support Act, saying they would lose audience members and revenue. Some groups are now circulating an online petition to their supporters to oppose the tax.
They're also questioning officials about what constitutes a "live performance" and if events like church concerts and school plays would be included in the tax.
Federal institutions such as the Kennedy Center and the Air and Space Museum would be exempt.
The D.C. Council is taking up the mayor's budget this week, although council members are sure to have a number of priorities to weigh when outlining a final budget.