At least 2,000 officers rallied wearing red armbands to distinguish themselves from civilians.
The officers, once feared for carrying out the repressive policies of their now exiled President Zine El Abidine Ben Ali, insisted they're not to blame for shooting deaths among protesters who forced the autocratic leader to flee after 23 years in power.
The U.N. human rights chief, Navi Pillay, has estimated more than 100 deaths have occurred during the unrest in Tunisia since mid-December, and is sending an assessment team to the North African country.
Meanwhile, Secretary of State Hillary Clinton has called on Tunisia's new leadership to enact speedy economic and political changes toward democracy.
The Associated Press contributed to this report.