WASHINGTON — It’s easy for Congress to meddle with the District of Columbia’s decision to legalize recreational use of marijuana, but taking on the states is a different matter.

A massive, catch-all spending bill Congress passed last week contains a provision preventing the District from using federal money to implement any law or regulation that repeals or reduces marijuana-related penalties. The action is in direct response to a voter initiative passed last month that allows possession of up to 2 ounces of pot or up to three mature plants for personal use.

The Constitution gives Congress the power to review and possibly reject all legislation approved by the District’s elected officials or its citizens.

Congress has less leverage with the states, and thwarting efforts supported by a plurality of voters back home could prove politically risky at election time.

“That’s sort of asking for a head-on collision with states’ rights,” said Philip Wallach of the Brookings Institution, a Washington-based think tank.