About 200 anti-war protesters on their way to the office of Sen. Joseph I. Lieberman (D-Conn.) clashed with Hartford police last month. Eighteen of the protesters were arrested—including Yale and Wesleyan University students.

As criminal charges proceed against the protesters—who face up to 10 years in prison—some warn activists elsewhere to beware what they see as crackdown on peace protests.

“The fact that dissent is being suppressed anywhere means that it could happen in your hometown,” said Wesleyan junior Abe J. Walker, one of the arrested students.

But recent protests at Harvard—from anti-war demonstrations to living wage rallies—have all been staged without incident.

A Sept. 20 peace rally organized by Harvard Initiative for Peace and Justice (HIPJ) attracted 500 students and, the Progressive Student Labor Movement (PSLM) held a rally at Holyoke Center on the day of the installation of University President Lawrence H. Summers.

Neither event resulted in any arrests.

Today, PSLM will play a large role in a rally billed as “Justice for Janitors” in front of the Science Center at 4 p.m. that is also expected to be peaceful in nature.

Steven G. Catalano, Harvard University Police Department (HUPD) spokesperson, said there have been no protest-related arrests in at least three years.

“We haven’t had an adversarial situation for a long time at Harvard, and we want to maintain that record,” Catalano said.

Even unauthorized, unannounced demonstrations have not resulted in arrests. Last spring’s three-week student takeover of Mass. Hall ended peacefully, and was marked by amicable relations between officers and students.

Catalano said that though HUPD demands prior approval for demonstrations, they try to avoid resorting to physical measures to stop protests.

“We encourage students, it’s part of their education, to express their opinions and beliefs, but we encourage them to do that in a structured way for the good of everyone involved,” Catalano said. “Student groups have to respect the rules that have been put into place.”

HUPD was present at the September peace rally on the steps of Widener Library are expected to be at today’s PSLM rally in front of the Science Center.

HIPJ member Mary M. Jirmanus ’05 attended the September rally and said she thought the police presence was low-key.

“We were not there to interfere. We are there to make observations and maintain a presence,” Catalano said.