The first time the University of Pittsburgh's campus was rocked by lawlessness, dimmed by smoke and littered with less-than-lethal ammunition, university Police Chief Tim Delaney wasn't in a position to do much about it.

Under the U.S. Secret Service plan for the Group of 20 summit, his emergency response officers were assigned on the night of Thursday, Sept. 24 to the area around Phipps Conservatory, where world leaders were dining.

Later, in the calm of the wee hours, he contemplated the impact of an evening of window-breaking by anarchists and general student bewilderment on a campus he is sworn to protect.

"I'm sitting there at 2:30 in the morning saying, 'How can I do better? What can I do?' " he said in an interview last week.

The answers he came up with -- warning students to stay close to their residences and encircling the Litchfield Towers dormitories with Pitt police, among others -- made him the man in the middle.

He continues in that role as he interviews arrested students and works with Allegheny County District Attorney Stephen A. Zappala Jr. to weigh whether charges should be dropped in certain cases. Students have until Tuesday to make arguments that they weren't illegally disobeying dispersal orders but simply got caught up in the confusion.

He is also, so far, one of the only people offering anything other than a black-and-white portrait of the Friday-night ruckus that has raised new questions about the border between police responsibilities and rights of expression.

"To say the cops overreacted, no," he said. But 12-hour police shifts, communication gaps, sophisticated "hooligans" and naive students combined to make for some difficult moments.

"It's all of it. It's all of it," he said. "But in the litigious society we live in, people are always afraid to say, 'Uh, yeah, I think you're right.' Nobody will admit to anything, because everybody's lining up to sue."

By Friday, Sept. 25, the borderline between free expression and crime in Pittsburgh already was subject to dispute. The American Civil Liberties Union had sued in U.S. District Court repeatedly, alleging city and federal suppression of rights to assemble and speak -- those suits are pending and the ACLU plans to seek damages -- and Oakland rang with such chants as, "This is what a police state looks like."

Chief Delaney got approval from Pitt's administration and student government to send emergency e-mails, texts and robocalls, advising students to stay near their residences. Some have criticized that decision as a move guaranteed to lure curious students into the streets. He said he weighed that prospect but decided he could not afford to risk having uninformed students wander naively into a potential confrontation.

"I try to protect the innocent," he said. "If you decide to do it on your own, I can't help you."

He also deployed around 60 officers, divided into seven "mobile field forces," primarily around the three Litchfield Towers, home to 1,800 students.

"An out-of-town police officer has no concept of what Tower B is," he said.

Around 10:30 p.m., police began to worry that their control of the situation in Oakland was tenuous, and Chief Delaney was having flashbacks to the night before.

"Thursday night, we had 18 businesses that were crushed, smashed," he said. "We couldn't have a second night of that, because it would just escalate."

Police began issuing dispersal orders at 10:42 p.m., driven by the sight of members of the crowd "masking up" with bandannas, he said. Some students, particularly freshmen, treated the situation as if it were a reality TV show, he said. Others challenged the right of the police to be on campus.

"I said, 'Dudes, this is a national special event," Chief Delaney said. "We don't have a wall around us. You can't think because you run on the Cathedral [of Learning] lawn or the William Pitt Union lawn that you're free of any laws.' "

Recordings of police scanner chatter from that night reveal the plan. A line of officers, anchored by visiting Miami police, on the Forbes Avenue side of Schenley Plaza would push south. A SWAT vehicle equipped with the disorienting Long Range Acoustic Device set up at Schenley Drive and Roberto Clemente Drive, at the southwest corner of the square.

Gas -- which Chief Delaney said was really just smoke and a light dose of Oleoresin Capsicum, a compound that causes tears, pain and even temporary blindness -- would be used. Then a "hammer and anvil" tactic was employed, in which a crowd is restrained by a stationary force and split by a mobile force.

"This is how we're going to push them, after we get the encirclement; after we get the encirclement, we're going to push them down Forbes, back towards Schenley Drive Extension," an unidentified police supervisor broadcast. "Leave Schenley Drive Extension open, so we can continue to push. Then we'll establish a skirmish line along Schenley Drive Extension."

It worked, said Chief Delaney, noting that there were no serious injuries or property damage Friday night.

But it did not go off without a hitch. The Miami police line needed last-minute reinforcements. Some units bunched up, leaving gaps that parts of the crowd broke through. A crowd flowed toward Bouquet Street, forcing police to move toward the crowd from the southwest.

Police brass worried aloud that they might end up in a situation in which they were pushing crowds around with no apparent end game. There were miscommunications, scrambles and sometimes turf tensions -- notably around the Towers dorms.

Scanner recordings indicate that police saw some people in the crowd run "through" or "inside" the Towers.

"We have a decent number encircled here," in the Towers, one unidentified officer broadcast. "We have them contained right now. If you stop and push in, right where the smoke is, that's where the crowd is. We can contain it right there."

It was already contained, according to Chief Delaney; his officers saw those people dash between the Towers to the Fifth Avenue side.

"We got the guys," he said. "It wasn't so much that we were halting, stopping [other police], or trying to do anything else. We already knew they were apprehended."

Non-university police, though, didn't appear to know that.

They talked of "clearing the elevator," and getting "those people contained so we can start a clearing element up those stairs if anybody got up in the upper floors." Chief Delaney said that effort was driven in part by rumors that anarchists were going to infiltrate the dorms and pull fire alarms, feeding the chaos.

Then came the counterorder from an unidentified officer over the radio: "All right, Pitt doesn't want us to make entry, so we're going to hold out here, and if they come out, we're going to arrest them."

Police from other agencies then tried to reach Pitt police by telephone but found that the phone they were trying to call "just can't receive incoming calls."

Communication difficulties, said Chief Delaney, were driven in part by the presence of both out-of-town officers and sophisticated antagonists. With so many departments involved in summit security, there was no way to completely encrypt radio communications. Then police saw their on-air orders popping up moments later on Internet sites like Twitter.com, prompting them to shift communication to cell phones.

"We wanted to talk without the whole world twittering us," he said

Debate continued on the radio over who had jurisdiction over the Towers, and whether to pursue perceived "trespassers" inside.

On the scanner tape, an unidentified city police official is heard making preparations to send in a tactical team. Assistant Chief Maurita Bryant then ordered city police to hold off until Deputy Chief Paul Donaldson could weigh in. A ranking Pitt officer arrived at the Towers, and the matter was resolved.

"Look at it logically," Chief Delaney said. "If people are running into the residence halls, unless they're wanted criminals, you want them off the street. Why are you going to go up into the residence halls to get them back down again?"

Over the course of the two-day summit, police saw anarchists employing novel tactics -- the use of the Internet to communicate police tactics, false 911 calls reporting things like a breach of the Carnegie Museums, quick changes from black garb to university gear, and radicals melting into the general population, the chief said.

Other plans apparently didn't come to fruition, he said, noting that Pitt janitors found in the bushes behind Heinz Chapel a large bag of fireworks -- an arsenal that, had it been deployed, could have set off confusion and calamity.

"The issue was, the combination of out-of-towners," he said. "Pittsburgh people are used to Pittsburgh people."

He said Pitt police had smoke but didn't use it, and they weren't using the rubber bullets or bean bag rounds used elsewhere in the city during summit policing. Watch video of the arrests made in Oakland, he said, and you'll see white plastic hand ties on those charged -- while his officers had only black hand ties.

Nonetheless, he has a list of 51 arrested Pitt students on his desk, angry parents and concerned lawyers on his phone, and -- thankfully, he said -- a reasonable district attorney.

"We made our own little criteria," for dropping charges, he said, explaining that charges won't be dropped for people who were arrested more than once or accused of serious offenses. Three double-arrestees -- among them a student arrested Sept. 24 at 34th Street and Penn Avenue, and the next day at Fifth Avenue and Tennyson Avenue -- will have their days in court, he said.

"I'm looking at kids who were trying to get to their rooms, who were trying to get home, who got trapped up."

He had interviewed 15 students by late Thursday. "I'm recommending dismissal for all 15," he said. Others have until Tuesday to come in and make their cases.

"We're trying to thin out the innocent."

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