"I love puppies!" "Caution: Chalk is dangerous." "Long chalk to freedom."

These were just some of the messages written by Harvard University professors on campus sidewalks on Tuesday, in opposition of new university policies restricting protests.

The updated "campus use" rules, announced on Aug. 1 by Executive Vice President Meredith Weenick, include stringent measures that could impact student demonstrations, such as the 20-day pro-Palestine encampment from last spring. Students now need administrative approval before engaging in activities like chalking sidewalks, pitching tents, putting up art exhibits or using public spaces, with potential consequences for non-compliance.

Among the rules are requirements for booking event spaces, ensuring the free flow of traffic, and guidelines on noise levels and event sponsorships. Harvard affiliates must also present valid university identification upon request by officials.

These rules, while aiming to maintain order and safety on campus, also provide the university with a mechanism to manage and potentially limit student demonstrations and other activities in shared spaces.

Regarding chalking specifically, the new policy states: "Individuals and organizations are not permitted to chalk, paint, engrave, or otherwise write or draw on any University property without prior written approval from the relevant Local Contact. Any such unauthorized markings will be removed by, or under the direction of, authorized University personnel."

In a colorful defiance of these rules, professors Steven R. Levitsky, Walter Johnson, Ryan D. Enos, Richard F. Thomas, and Hibah Osman chalked messages under the John Harvard statue, expressing concern that the rules threaten free speech, according to The Harvard Crimson, the school's student newspaper.

"Welcome students," read one message. Another read: "Ask why chalking is banned."

In a statement to the Crimson, Johnson said, "The number of rules limiting and defining the boundaries of acceptable expression made by the university administration over the summer is dizzying. Their approach seems to be to assert incredibly broad authority over expression which then allows them a great deal of latitude to selectively enforce regulations."

The messages were washed away within an hour.