Since the September 11 attacks on New York and Washington, Mehmet Elkatmis said "the United States has distanced itself from the principles of freedom".
Speaking at a seminar on Thursday organised by the International Federation for Human Rights (FIDH), he said Washington had "committed genocide" in the countries where it had intervened militarily in the two years since the 2001 attacks.
It had also tortured prisoners, he said, including some 600 al-Qaida suspects held at the Guantanamo Bay US naval base in Cuba.
Many of the Guantanamo prisoners have been detained for almost two years since their capture during the US-led war in Afghanistan, without being charged or given access to legal advice.
Washington is now "in no position to speak about human rights", added Elkatmis, who is a member of Turkey's ruling Justice and Development party.
The global rights federation also warned of growing abuses in the wake of September 11.
"Under the pretext of combating terrorism and deterring its organisers, repression has been increasing for the past two years," it said.