The secretary-general says he is now considering the report and will then pass it on to Guinea's military government, the African Union, the Economic Community of West African States, and the U.N. Security Council.
The three-member commission spent ten days in Conakry hearing testimony from security officials and opposition demonstrators who were at the national stadium September 28.
Local human rights groups say dozens of women were raped and at least 157 people were killed demonstrating against the expected candidacy of military ruler Captain Moussa Dadis Camara. His government says 57 people died, most in the crush of people fleeing the stadium.
Now that the U.N. commission has finished its report, human rights leaders in Guinea say the international community must hold accountable those responsible for the violence.
Tierno Madjou Sow is president of Guinea's Human Rights Organization. He says the military government has committed crimes against humanity to be brought before the International Criminal Court.
Sow says he is certain the violence of September 28 was organized because many civilian and public security officials have testified about how it was pre-planned. Sow says you can see how it was premeditated in the way it was carried out, in the way that protesters were allowed to enter the stadium, then all of the doors were closed.
Aliou Barry heads Guinea's national observer group on human rights.
Barry says what is important is that there is a phenomena of impunity in Guinea that does not punish people responsible for human rights violations. People who torture live together with their victims. Since September 28, Barry says no one has been arrested. And victims are afraid, especially women who have given testimony about being raped.
In addition to the U.N. investigation, Guinea's military government has its own inquiry. That commission's president, Sirman Kouyate, says the group has already heard testimony from opposition leaders, civil society leaders, and security chiefs.
Kouyate says the commission of inquiry's sub-committees have now begun their work on the ground to investigate what happened.
But the commission raised questions this week when the head of its sub-committee investigating rape said there were no confirmed cases of sexual assault reported at the Donka National Hospital.
Because she says most of the women who claim to have been raped waited more than one month to seek medical treatment, subcommittee chair Pierrette Tolno says the commission now concludes there were no confirmed cases of rape relating to September's violence.
Corinne Dufka heads the West Africa office for Human Rights Watch.
"There were a number of women who actually did seek medical treatment according to doctors who I interviewed at Danka Hospital. They said they treated three or four women for splinters, for hemorrhages secondary to being raped with sticks or guns or other objects. So women did get treated in the hospital," said Dufka.
Human Rights Watch Thursday released the most comprehensive report to date on the September 28 killing. It says the violence was an organized, premeditated operation by members of the presidential guard, gendarmes, police, and civilian militia.
Captain Camara blames the violence on both his political opponents and what he calls "uncontrollable elements" of the military.
The former head of the presidential guard says he shot Captain Camara in the head two week ago because the captain was trying to blame him for the September violence. In an interview with French radio, Lieutenant Aboubacar Diakite says he will not turn himself in because he believes he will be killed to cover-up what happened September 28.
Captain Camara is recovering in a Moroccan military hospital. There has been little news about his condition and no official word on when he might return to Guinea.