The defendants in Monday's trial before Skopje's District Court are charged with staging a bogus anti-terrorist action that killed six Pakistani Muslims and an Indian Sikh to promote Macedonia as a player in the US-led "war on terror".
The police action in March 2002 triggered international criticism of the Balkan country and strained relations with Islamabad.
According to the indictment, the four men lured the foreigners - believed to be illegal immigrants trying to get into nearby European Union countries - into Macedonia, accused them of being "terrorists" and killed them in a village near Skopje.
At the time, police said the seven had been planning to attack Western countries' embassies in Skopje and linked them to al-Qaida.
They also claimed that religious texts found on the Pakistanis were evidence of their terrorist intentions.
However, in May this year police acknowledged that the killings were part of a plot by senior police officials to "present themselves as participants in the war against terrorism and demonstrate Macedonia's commitment to the war on terror".
The four defendants include police General Goran Stojkov, intelligence officer Aleksandar Cvetkov, the former commander of a now disbanded special police unit, Boban Utkovski, and businessman Mitko Kikerkov.
Former interior minister Ljube Boskovski was initially also charged as the main organiser of the slaying but fled to Croatia. He is in detention in the coastal Croatian town of Pula and the case against him will be handled by authorities there.
Before the trial, the defence lawyers said their clients were innocent and victims of politically motivated proceedings that were part of "political revenge" by the new Macedonian government.
Sources at the court said at least 30 witnesses will testify during the trial.
The defendants face sentences of up to 20 years in prison if found guilty.