Boston Mayor Marty Walsh is demanding that the head of the state gaming commission recuse himself from the vote over an eastern Massachusetts casino.

Lawyers for the Walsh administration made the demand in a letter to commission chair Steve Crosby. It says Crosby made “prejudicial” statements about Boston’s legal standing as a “host community” for casino proposals just outside the city limits, in Everett and Revere.

Host community status would mean Boston could veto the projects, and – if one is built – get a larger chunk of money.

Walsh has claimed that Boston voters in the Charlestown and East Boston neighborhoods have a right to vote on whether a resort casino can be built on their borders.

The commission has set up a month-long process to sort out the claims.

The letter accuses Crosby of “stacking the deck” against Boston and denying the city a fair hearing.

In a statement, the spokesperson for gaming regulators says the commission will not be “distracted by the politicizing of the process.”