Massachusetts Gov. Deval Patrick has publicly stated that he is friendly with Gates and Charles Ogletree, another Harvard University professor who is acting as Gates' attorney.
Simmons has said she is "outraged" at the arrest of Gates, who she also knows socially.
The remarks have raised questions about politicians intervening on Gates' behalf.
A spokesman for Middlesex County District Attorney Gerry Leone insisted that political influence did not play a role in the case.
"Once a complaint is issued it can be dropped at anytime," said the spokesman, Corey Welford.
Leone brokered a meeting between Ogletree and Cambridge police officials to see "if the case could be resolved,'' Welford said. "The district attorney agreed to drop the charges after an agreement was made between the Cambridge Police Department and Gates' attorney.''
At a press conference Tuesday, Downes said that she still believed there was "probable cause" for Gates' arrest.
"I think what went wrong personally is that you had two human beings that were reacting to a set of circumstances, and unfortunately at the time cooler heads did not prevail," said Downes.
"I think both parties were wrong," said Downes. "I think that's fair to say. It wasn't Professor Gates' best moment, and it was not the Cambridge Police Department's best moment."
Gates, who according to his lawyer had been trying to force open a jammed door, was inside the house when the Cambridge police officer got there.
Asked about allegations that Gates' arrest was racially fueled, Downes said, "Our position is very firmly that race did not play any factor at all in the arrest of Mr. Gates."
Though Gates eventually identified himself, he was arrested after he allegedly came out of the house and continued yelling at police, even after he was warned that he "was becoming disorderly," according to the police report.