Two different investigations have found dozens of cases in Colorado of welfare money going for pot, and some lawmakers fear the same thing could happen in Washington state this summer when the first legal cannabis stores open.
U.S. Rep. Dave Reichert of Washington state calls the problem infuriating. He says more than $5,000 in welfare benefits have been withdrawn so far at stores that sell marijuana in Colorado.
"What's sad is that you always have people out there who take advantage of these benefits, and so ... I feel part of my whole responsibility is to look out for those people who really need the benefits," he said.
Using welfare benefits for liquor, casinos and at strip clubs is already against the law, with states required to show how they're tracking that. A new bill would expand the prohibition to pot shops.
The problem is that welfare benefits are often turned into cash at ATM machines using electronic cards that recipients get - which makes it very difficult to control or track how the money is used.
"There are always going to be people who are gaming the system, and it's our responsibility as a state to ensure that we're doing something to look for that kind of fraud," says Babs Roberts, community services director with the state Department of Social and Health Services.
But she admitted that currently there is nothing to prevent welfare recipients from using cash obtained through the electronic cards to buy marijuana.
Roberts tells KOMO News they'll have to work with the federal government to make sure they are in compliance with any new legislation.