Complaints against the Metropolitan Police have risen by 17% in a year, according to new figures.
They went from 6,144 in 2008-09 to 7,175 in 2009-10, Independent Police Complaints Commission [IPCC] statistics show. The UK average rise was 8%.
The Met claimed the rise was because "public confidence in the complaints procedure is increasing".
But Green Party London Assembly Member Jenny Jones said it was also "because there was more to complain about".
Asked whether the public would believe the Met's claim the rise was down to people being more confident about complaining, she said: "There is an element of that.
"But it is also because there was more to complain about.
"When you kettle thousands of people a proportion of those will complain - and quite rightly."
Ms Jones, who sits on the Metropolitan Police Authority, added: "They certainly have done some pretty stupid things."
The period covered by the new figures includes the day of the G20 protest, on 1 April 2009, which led to widespread criticism of police tactics.
Newspaper seller Ian Tomlinson died after being pushed to the ground by an officer.
A Met spokesman said: "The rise can be attributed to a number of factors.
"The IPCC has expressed a view that an increase in complaint allegations is an indicator that public confidence in the complaints procedure is increasing.
"The MPS (Metropolitan Police Service) shares this view and strongly encourages the reporting of complaints."
He added: "We expect the highest standard of professionalism from our officers and any allegation that conduct has fallen below this is treated extremely seriously."