A House Republican vote to block decriminalized marijuana in the District of Columbia could have a big unintended consequence: effectively legalizing pot in the nation's capital.

Here's the story: DC's decriminalization law ends the $1,000 fine and one-year jail sentence that was previously attached to marijuana possession. But it doesn't totally legalize marijuana. Instead, it authorizes a $25 civil fine for marijuana possession and allows the seizure of the drug. It also prohibits public pot use with the threat of a 60-day jail penalty, similar to open-container laws that bar public alcohol consumption.

That would leave DC with decriminalization but no ability to enforce civil fines or jail time

Congress holds power over DC's budget. And House Republicans don't want to allow DC to decriminalize marijuana. So House Republicans passed a measure blocking funding for DC's decriminalization law.

The problem? The only parts of the law that require funding are the penalties for possession and the enforcement of the public-use ban. Eliminating the previous criminal penalties, by contrast, costs nothing.

So by preventing funding for DC's decriminalization law, House Republicans could end enforcement for the few penalties that remain. That would leave DC with decriminalization but no ability to enforce civil fines or jail time — something that looks very similar to outright legalization.

A spokesperson for the mayor acknowledged the possibility of the measure backfiring, but he cautioned that the issue is far from settled and still under review. In the next couple days, the city's lawyers will work through the measure to see how it would affect DC's decriminalization law and the city's medical marijuana program — and whether it could really lead to de facto legalization.

Another hurdle for the measure is that the Republican-controlled House and Democratic-controlled Senate will need to agree on what will get approved, changed, or rejected in DC's budget, including House Republicans' anti-decriminalization measure, before the bill becomes law.

At this point, it's difficult to predict how the negotiations will play out. In the past, Democrats have been less supportive than Republicans of interfering in DC's local governance. But marijuana is still very much a touchy political topic, so it's difficult to predict where the Senate will ultimately land on this particular issue.

Update: This article was edited after it was published for length and clarity.