The trial in the legal challenge by some state attorneys general to the T-Mobile-Sprint merger began Monday (Dec. 9) in a New York district court.

T-Mobile and Sprint have pledged not to close their deal until the state AG suit is resolved. The deal has been approved by the FCC and passed antitrust muster--with conditions--at the Justice Department.

Related: More States OK with T-Mobile-Sprint

“The megamerger of T-Mobile and Sprint would reduce competition in the mobile marketplace and be bad for consumers, bad for workers, and bad for innovation," said New York attorney general Letitia James, who along with California AG Zavier Becerra, were the lead states on the suit. "We simply must protect consumers from unchecked corporate dominance and make sure competition in the marketplace yields better outcomes for cell phone customers and workers alike.

Becerra said the merger would hurt consumers and said he was confident they had the law on their side.

Related: Civil Rights Groups Strike Deal with T-Mobile-Sprint

The government says that the combo creates a stronger number three competitor to Verizon and AT&T given that the DOJ settlement requires it to  spinoff pre-paid wireless operator Boost Mobile to Dish, which they say will morph into a fourth facilities-based carrier. The AGs argue that it will instead reduce competition with no guarantee that Sprint will ever morph into a new "uncarrier."

Joining California and New York in the suit are Connecticut, Hawaii, Illinois, Maryland, Massachusetts, Michigan, Minnesota, Oregon, Pennsylvania, Virginia, Wisconsin, and the District of Columbia .

A number of other states including Colorado, Florida, Kansas, Louisiana, Nebraska, Ohio, Oklahoma, Nevada, South Dakota and Texas have joined DOJ's settlement approving the deal with conditions. 

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