Insisting the city of Boston should be considered a host community for the planned casino in neighboring Everett, Boston Mayor Marty Walsh on Monday filed a lawsuit against the state Gaming Commission with the goal of allowing Charlestown residents to vote on the project and negotiating a substantial mitigation package.

Filed in Suffolk Superior Court, the suit is the latest volley in a battle between Walsh and the five-member Gaming Commission, which in November formally awarded an eastern Massachusetts casino license to Wynn Resorts. Wynn won out over Mohegan Sun, which was seeking to build a casino on Suffolk Downs property in Revere.

"To protect the people of Boston and ensure the safety of our neighborhoods, it is clear to us that this is the best and only way to move forward for Charlestown, for the city of Boston and for the entire Commonwealth," Walsh said at a press conference announcing the lawsuit, which calls for nullifying the license for Wynn.

Walsh said the city has been unable to come to a consensus with Wynn about the impact on Boston of the planned $1.6 billion casino, which will be situated on the Mystic River in Everett.

Two other cities - Somerville and Revere - have also filed lawsuits over the awarding of the license.
A Gaming Commission spokeswoman did not have immediate comment on the city's suit. The commission is set to meet on Thursday at the Boston Convention and Exhibition Center at 10:30 a.m.

The lawsuit alleges the location of the Wynn Resorts casino has only one legal entry and exit through the city of Boston, arguing that Boston will feel the "lion's share" of the impact of environmental, public safety and traffic issues.

The lawsuit also alleges that after a hearing to determine the city's legal status as a host or surrounding community, the Gaming Commission "manipulated the outcome of the hearing by withholding documents from the City that had direct bearing on Boston's host community status, advocating on behalf of Wynn, and deliberating and predetermining the outcome outside the public hearing context, in violation of the Open Meeting Law and the Gaming Act."

The lawsuit, which makes a litany of claims about the site's suitability, also argues that Wynn has failed to follow through on its promise to the Gaming commission to create access to the casino through Everett on land owned by the MBTA within 60 days of the award of the license.

Thomas Frongillo, an attorney hired by the city, added that the criminal indictments announced in October in connection with the Everett parcel should have led to the commission to disqualify Wynn's bid for the casino license. Federal authorities have charged three men with attempting to hide from Wynn Resorts and gaming regulations the financial interest of a felon in the 33-acre parcel.

The lawsuit also claims the commission set "nominal" traffic mitigation conditions on Wynn.

"The Commission's traffic mitigation conditions are wholly contrary to the City's planned use of its streets in Charlestown," the lawsuit says. "The Commission was required to impose conditions that would mitigate traffic. This necessitated the imposition of conditions requiring Wynn to re-route casino traffic away from Rutherford Avenue and Sullivan Square. Instead, the Commission imposed conditions that will do nothing to prevent the exacerbation of existing congestion by introducing thousands of additional vehicles to the area."

The lawsuit was filed by the city's corporation counsel, former Rep. Eugene O'Flaherty, and attorneys at Fish & Richardson P.C.

Wynn announced hours earlier that it had finalized the purchase of the Everett Land.