By Adam Vaccaro

Boston.com Staff | 01.05.15 | 5:07 PM

Boston is the latest city to sue the Massachusetts Gaming Commission.

Mayor Marty Walsh announced the city’s suit, challenging the commission’s awarding of the sole Boston-area casino license to a Wynn Resorts project in Everett, at a Monday afternoon press conference.

Walsh feuded with the commission throughout 2014, as he argued Boston should be considered a host community for the Wynn proposal—and for the proposed Mohegan Sun project in Revere that lost out on the casino license to Wynn—but was rebuffed by the gaming commission in that effort. Had Boston been considered a host community, residents of adjacent neighborhoods (Charlestown, in the case of the Everett proposal) would have been able to vote on whether to allow the casinos to be built, and the city would have been able to negotiate lucrative ‘host city’ agreements with the gambling companies.

Walsh later reached a ‘surrounding community’ agreement with Mohegan Sun, but failed to reach an agreement with Wynn. In the process of awarding Wynn the casino license, the gaming board built in some mitigation payments to Boston, but they paled in comparison to the Mohegan Sun haul. Walsh has since said he was still hopeful about reaching an agreement with Wynn, but has not reached an accord.

The city’s lawsuit, filed in Suffolk Superior Court, asserts that Boston deserves host community status for providing access to the casino through Charlestown. (Wynn has said it plans to build an access road that avoids Boston, but as of yet that’s no sure thing.)

Aside from the access road, the suit says that Sullivan Square and Rutherford Avenue will also take on new traffic from the casino. It claims the gaming commission and Wynn have not moved to properly mitigate that traffic, and says that is evidence that the surrounding community agreement process was unfair to the city.

In an emailed statement, Walsh said: “We have understood from day one the complexity of this issue as it relates to the City and it has always been our belief that Boston is a host community. Our priority is to protect the people of Boston and ensure the safety of our neighborhoods. It is clear to us that this is the best way to move forward for Charlestown, the City of Boston and the entire Commonwealth.”

If Boston received host community status, residents of Charlestown could get the chance to vote on whether the casino could move forward—giving the city leverage to negotiate a better deal with Wynn.

However, the lawsuit also challenges whether the casino should even be built in the first place, and whether Wynn legally received its license, by pointing to issues with the site’s property ownership. In October, two of the former Monsanto site’s owners were indicted for allegedly concealing the ownership stake of convicted felon Charles Lightbody. (Lightbody was also indicted in October.)

Earlier Monday, Wynn announced it had finalized its purchase of the Everett land.

The Massachusetts Gaming Commission declined to offer an immediate comment Monday afternoon, saying it had not yet been served with a suit.

Boston is the third city to sue the board over the Wynn decision. The two others are Revere, which lost out on hosting a casino, and Somerville, which like Charlestown is close to the Wynn project and whose mayor fought against allowing casinos in Massachusetts. Those two suits also challenge the legality of the Wynn license in light of Lightbody’s alleged property ownership stake.