Rob McKenna

This blog post has been updated

Washington Attorney General Rob McKenna and attorneys general from six other states are joining the U.S. Department of Justice’s antitrust lawsuit to block the AT&T takeover of T-Mobile USA.

McKenna said T-Mobile plans have typically cost less per month than comparable AT&T plans, and the merger raises “serious concerns” about higher prices for consumers. Seattle, Tacoma and Spokane would become particularly uncompetitive because of a high level of market concentration if the deal were to go through, McKenna said.

McKenna’s office said the merger would add 34 million customers to AT&T’s 96 million, “giving it a combined market share of 43 percent, well ahead Verizon’s 34 percent.”

The move to oppose the AT&T-T-Mobile deal puts McKenna, who is running for governor, at odds with Microsoft, which has joined other tech titans such as Facebook and Oracle in supporting the merger. A merger also could impact Washington's economy. Critics of the merger fear it could cause job losses at T-Mobile’s Bellevue headquarters, which employs about 5,000 workers.

Here is a statement from McKenna's announcement Friday:

This merger will result in less competition, fewer choices and higher prices for Washington state consumers. If the deal goes through, two companies will control roughly three quarters of mobile subscribers in the U.S. Antitrust laws exist to prevent such strangleholds over products and services.

McKenna said the merger also would give AT&T a monopoly over Global System for Mobile (GSM) technology, with is the most popular technology for consumers and businesses that need their phones to work internationally.

AT&T and T-Mobile are the only major carriers to utilize GSM, McKenna said.

McKenna had previously issued civil investigative demands, similar to subpoenas, for information, about the proposed merger.

U.S. Rep. Jay Inslee, D-Wash., in letters to the CEOs of AT&T and T-Mobile, voiced concerns over the merger. Inslee is running for governor against McKenna, who is a Republican.

The other attorneys general joining the Justice Department’s suit to block the deal are from New York, California, Illinois, Massachusetts, Ohio and Pennsylvania.

McKenna and the six other state AGS joining the Justice Department lawsuit come as a contrast to 11 other attorneys general -- from states including North Dakota, South Dakota, Utah, West Virginia and Wyoming -- who in July came out in favor of the AT&T-T-Mobile merger. Politicians from many rural areas applaud the merger, saying it would position AT&T to create more spectrum and also expand broadband service to neglected small towns and rural areas.

Meanwhile, AT&T rival Sprint Nextel applauded McKenna and others jumping into the fray to block the deal. Vonya McCann, Sprint Nextel’s senior vice president for Government Affairs, issued a statement:

After a comprehensive review of the facts related to AT&T’s proposed takeover of T-Mobile, seven state attorneys general have reached the same conclusion as the U.S. Department of Justice: This proposed takeover violates antitrust law and would harm consumers, competition and our nation’s economy. This is a strong stand for American consumers, and Sprint commends this bipartisan group of state attorneys general for joining with the U.S. Justice Department to protect consumers, competition and American jobs.

Sprint has sued to block the AT&T-T-Mobile merger.

In late August, The Justice Department filed an antitrust lawsuit to block AT&T’s proposed $39 billion takeover of T-Mobile.

In court papers, the DOJ said an acquisition of the country’s fourth largest wireless carrier by AT&T, the second largest wireless carrier, would reduce competition and raise prices.