© Eric Gay/Associated PressDallas police chief David Brown, front, and Dallas mayor Mike Rawlings, rear, talk with the media during a news conference in Dallas.
President Barack Obama later eulogized the slain officers, saying they died while defending essential constitutional rights.
But nearly two months after the shootings, Dallas police have moved to silence critics and squelch lingering questions about the attack. Officers in riot gear have been told to ticket protesters who block or disrupt traffic, and Police Chief David Brown has refused to meet with demonstrators unless they agree to end their marches through downtown, which he says pose a threat to officers.
Authorities have also refused to release even the most basic information about the slayings, including any details about the weapons used, the autopsy findings and ballistics tests that could establish whether any officers were hit by friendly fire. Police have indicated that such information could be withheld almost indefinitely.
In addition, the police department's most vocal, visible critic — a 27-year-old self-styled preacher with a criminal history — has been arrested multiple times in the last month on warrants that include unpaid traffic tickets and attempts to revoke his probation from a 2009 felony. On Friday, Dominique Alexander was ordered to prison.
"Why all of a sudden are we the target?" asked Damon Crenshaw, vice president of the Next Generation Action Network, which organized the July 7 protest. "We're not protesting because we're mad at them. We're protesting because the problems still exist and they won't talk to us."
Crenshaw said Alexander was targeted because of his protest activities and that the shooter, Micah Johnson, was not affiliated with their group.
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