We've tried this route before. In 2007, then-Gov. Martin O'Malley convinced the legislature, which had blocked legalization of slots during the term of his Republican predecessor, Robert L. Ehrlich Jr., to put the matter on the ballot as a constitutional amendment — not because it was necessary to amend the constitution but because it broke the political logjam in Annapolis. One of the talking points at the time was that it would protect Marylanders from further expansion of gambling by enshrining the details in the constitution. That protection didn't mean much; gambling interests managed to get an expansion back on the ballot a mere four years later in what proved to be the most expensive (by far) public campaign around any election issue in Maryland history, with dueling casino giants spending tens of millions to persuade the public. Putting the issue in the constitution also meant that other details, like the precise number of slot machines, the locations where casinos could be built and the precise uses for the taxes they generated could only be changed through another amendment.