What happened

The future of American marijuana companies is directly tied to decriminalization. After all, the wider the market for their products, the brighter their prospects. On Monday, however, it appeared that the top-down push for finally making marijuana de facto legal had hit yet another stumbling block. As a result, investors traded out of selected U.S. pot titles; one victim was Curaleaf (CURLF -5.37%), which tumbled by just over 4% on the day.

So what

It seems that two lawmakers in the House of Representatives have suddenly become concerned about the marijuana industry's possible effects on the environment. Earl Carter of Georgia and Doug Lamborn of Colorado, both Republicans, expressed this concern in a co-signed letter sent to the Environmental Protection Agency, plus the government's departments of Energy and Interior.

Citing The Washington Examiner, which had apparently received a copy of the letter, MJBiz Daily quoted the two Representatives as writing that "they have reservations regarding marijuana cultivation's subsequent emissions and believe more research is needed on this industry's rapidly growing demands on our country's energy systems."

Carter and Lamborn have asked the recipients to provide "detailed responses" by Nov. 30 to a set of questions addressing these concerns.

This is in response to the Cannabis Administration and Opportunity Act (CAOA) introduced by Democrats in the Senate in July.

Now what

Since Curaleaf is a top multi-state operator (MSO) and thus in the thick of the pot industry, it would be one of the entities directly affected by any obstacles on the road to federal decriminalization.

Given the widespread support decriminalization enjoys, it's still puzzling that some legislators are determined to throw roadblocks in its way. At some point decriminalization is very likely to happen, but news like this makes it seem like decriminalization is going to occur later, rather than sooner.