Isabelle Arradon – It is always difficult to say when an armed conflict is truly "over".

Even after the guns have stopped firing and the casualties have stopped piling up, wounds still linger – family members do not know what has happened to their loved ones, perpetrators of horrific crimes escape justice, and survivors struggle through lost homes and livelihood. This is true all over the world, and no less in Indonesia.

The devastating Aceh conflict may officially have ended with the 2005 peace accord between the Free Aceh Movement (GAM) and the government, but victims and communities there are still living with the consequences today.

Fifteen years ago – on Feb. 3, 1999 – one of the conflict's worst massacres took place. Just past midnight, a military unit opened indiscriminate fire on thousands of people who were returning home after attending a rally at the Matang Ulim village in Idi Cut, East Aceh – ostensibly a revenge attack for the nearby kidnapping and killing of ten army personnel a month before. At least seven people were killed that night and dozens wounded. To cover their tracks, soldiers reportedly tied the bodies with barbed wire, put them into sacks and dumped them in a nearby river.

Fifteen years later, no one has yet been held to account for the killings in Idi Cut – this is sadly emblematic of the Aceh conflict as whole, and of many other of Indonesia's past conflicts. In Aceh, the conflict remains an open wound – the fate of many of those killed is still unknown, perpetrators of human rights abuses walk free, and governments' attempts to provide reparations to those affected by the conflict have been piecemeal and limited at best. This is a situation Amnesty International highlighted in a report last year – Time to Face the Past – that examined the government's failure to provide the justice, truth and reparations victims of human rights abuses during the Aceh conflict are entitled to under international law.

It has been an uphill struggle for the many human rights groups and activists who have been fighting for the rights of the tens of thousands of victims and their family members. There has been a blatant lack of political will to tackle crimes of the past.

On the national stage, there has been a lack of progress in addressing past abuses, in particular during President Susilo Bambang Yudhoyono's two terms in office ending this year. The central government has failed to enact a new national truth commission law, after it was struck down by the Constitutional Court in 2006, and there has yet to be a comprehensive reparation program specifically aimed at addressing the harm suffered by victims and families of crimes under international law over the last decades.

Furthermore, many victims in Aceh feel they have been abandoned by the international community, especially the European Union and the Association of Southeast Asian Nations, who played a key role in the peace process.

But in December 2013, there was a historic breakthrough. The Aceh House of People's Representatives passed the Aceh Truth and Reconciliation bylaw on Dec. 27 that calls for the establishment of a truth commission. Although the bill is far from perfect, it shows that through political will, in this case Acehnese legislators, there can be concrete steps to address the past.

This Aceh truth commission could go a long way toward understanding the circumstances that led to past violations, learning from the past to ensure that such crimes will not be committed again, and ensuring that shared experiences are acknowledged, known and preserved. It is now up to the Acehnese and central governments to ensure that the bylaw is implemented at the earliest opportunity and that the commission operates in line with international standards.

The Acehnese legislature has set an example that the rest of Indonesia should take note of. A national truth and reconciliation law should be top of the political agenda. Hundreds of thousands are still waiting for truth and justice from Indonesia's many past conflicts – such as during the events of 1965-66, the May 1998 riots, and the conflicts in Papua and Timor-Leste (formerly East Timor).

Addressing these past crimes would not only contribute to healing the open wounds of the civilian population, it would also go a long way toward ending the general mistrust people across the country will feel towards authorities and the judiciary, as long as the complete impunity for serious human rights violations remains.

In April and July, Indonesians will be electing a new legislature and president – but while campaigning is already underway, addressing crimes of the past has disappointingly largely been absent. This is not an issue that should be swept under the carpet, but one that should take front and center stage in the debate. The Acehnese legislature has shown what is possible – it is time for the rest of Indonesia to follow suit.

[Isabelle Arradon is Amnesty International's deputy Asia-Pacific director.]