Government's star witness takes the stand in marathon day of AT&T trial

Economist Carl Shapiro said his analysis of AT&T's purchase of Time Warner shows that US consumers could together pay an additional $571 million in the year 2021 if the deal is approved.

"The merger will in fact harm consumers and the harm is significant in terms of the dollar amount," Shapiro testified.

Shapiro, who is also a professor at UC Berkeley, outlined three main reasons why he has concluded AT&T's proposed acquisition of Time Warner would be anti-competitive. Shapiro said his research and analysis show the merger would increase the cost to other distributors of the networks owned by Time Warner subsidiary Turner; the merged company could coordinate with Comcast-NBCUniversal to block their programming from emerging online distributors; and AT&T would be incentivized to restrict other distributors' use of HBO as a promotional tool to attract or retain customers for rival distributors Much of Shapiro's analysis had already been introduced in the pre-trial brief presented by the government and was cited frequently by government attorneys as they questioned the previous 18 witnesses.

Shapiro was the government's final witness.