Just two weeks before the Inter-American Commission on Human Rights is expected to release its final report on the case of 43 missing students in Mexico, a group of independent experts appointed by that commission are lamenting the government\u0026#039;s lack of cooperation and claiming that key evidence has gone missing or been destroyed.The 43 students from Ayotzinapa teachers\u0026#039; college in the Mexican state of Guerrero were attacked by local police on September 26, 2014. Six people were killed. The police then allegedly turned the students over to the organized crime group Guerreros Unidos. They have been missing ever since. The case, and the subsequent lack of answers, has spurred protests and outrage across the country.The human rights advocates began investigating the case in March, at the request of the victims\u0026#039; families. The group\u0026#039;s final report is due on September 6.According to Reuters:[I]n a news conference on Monday they said that they had not been allowed to speak to military personnel from the 27th infantry battalion, based in the southwestern city of Iguala, where the students disappeared.Instead, the military personnel, whom the IACHR believes may have witnessed disappearances, could only be questioned via a written questionnaire, which the team opted against submitting.BBC explains:Investigators from the IACHR want to question soldiers from the battalion in Iguala that responded to events at the time the students clashed with police.Relatives believe the soldiers may have failed to act as the police opened fire on the students and later bundled them onto a bus.In addition, TeleSUR reports, both security footage and clothes belonging to the victims, allegedly found at the scene, appear to have been mishandled by Mexican authorities.