Gates had forced his way through the front door because it was jammed, his lawyer said. Colleagues call the arrest last Thursday afternoon a clear case of racial profiling.
Cambridge police say they responded to the well-maintained two-story home after a woman reported seeing "two black males with backpacks on the porch," with one "wedging his shoulder into the door as if he was trying to force entry."
By the time police arrived, Gates was already inside. Police say he refused to come outside to speak with an officer, who told him he was investigating a report of a break-in.
"Why, because I'm a black man in America?" Gates said, according to a police report written by Sgt. James Crowley. The Cambridge police refused to comment on the arrest Monday.
Gates - the director of Harvard's W.E.B. Du Bois Institute for African and African American Research - initially refused to show the officer his identification, but then gave him a Harvard University ID card, according to police.
"Gates continued to yell at me, accusing me of racial bias and continued to tell me that I had not heard the last of him," the officer wrote.
Gates said he turned over his driver's license and Harvard ID - both with his photos - and repeatedly asked for the name and badge number of the officer, who refused. He said he then followed the officer as he left his house onto his front porch, where he was handcuffed in front of other officers, Gates said in a statement released by his attorney, fellow Harvard scholar Charles Ogletree, on a Web site Gates oversees, TheRoot.com
He was arrested on a disorderly conduct charge after police said he "exhibited loud and tumultuous behavior." He was released later that day on his own recognizance. An arraignment was scheduled for Aug. 26.
Gates, 58, also refused to speak publicly Monday, referring calls to Ogletree.
"He was shocked to find himself being questioned and shocked that the conversation continued after he showed his identification," Ogletree said.
Ogletree declined to say whether he believed the incident was racially motivated, saying "I think the incident speaks for itself."
Some of Gates' African-American colleagues say the arrest is part of a pattern of racial profiling in Cambridge.
Allen Counter, who has taught neuroscience at Harvard for 25 years, said he was stopped on campus by two Harvard police officers in 2004 after being mistaken for a robbery suspect. They threatened to arrest him when he could not produce identification.
"We do not believe that this arrest would have happened if professor Gates was white," Counter said. "It really has been very unsettling for African-Americans throughout Harvard and throughout Cambridge that this happened."
The Rev. Al Sharpton is vowing to attend Gates' arraignment.
"This arrest is indicative of at best police abuse of power or at worst the highest example of racial profiling I have seen," Sharpton said. "I have heard of driving while black and even shopping while black but now even going to your own home while black is a new low in police community affairs."
Ogletree said Gates had returned from a trip to China on Thursday with a driver, when he found his front door jammed. He went through the back door into the home - which he leases from Harvard - shut off an alarm and worked with the driver to get the door open. The driver left, and Gates was on the phone with the property's management company when police first arrived.
Ogletree also disputed the claim that Gates, who was wearing slacks and a polo shirt and carrying a cane, was yelling at the officer.
"He has an infection that has impacted his breathing since he came back from China, so he's been in a very delicate physical state," Ogletree said.
Lawrence D. Bobo, the W.E.B Du Bois Professor of the Social Sciences at Harvard, said he met with Gates at the police station and described his colleague as feeling humiliated and "emotionally devastated."
"It's just deeply disappointing but also a pointed reminder that there are serious problems that we have to wrestle with," he said.
Bobo said he hoped Cambridge police would drop the charges and called on the department to use the incident to review training and screening procedures it has in place.
The Middlesex district attorney's office said it could not do so until after Gates' arraignment. The woman who reported the apparent break-in did not return a message Monday.
Gates joined the Harvard faculty in 1991 and holds one of 20 prestigious "university professors" positions at the school. He also was host of "African American Lives," a PBS show about the family histories of prominent U.S. blacks, and was named by Time magazine as one of the 25 most influential Americans in 1997.
"I was obviously very concerned when I learned on Thursday about the incident," Harvard president Drew Gilpin Faust said in a statement. "He and I spoke directly and I have asked him to keep me apprised."