Cradling a framed portrait of her slain daughter, Payao Akkhahad approached a soldier outside a barracks in this vast Asian metropolis and delivered a letter asking for something her bereaved family feels it never got: justice.

Her only daughter, Kamolkate, was working as a volunteer nurse when gunmen fired into a Buddhist temple complex that was supposed to be a safe haven. She was killed May 19, 2010 — the final day of militant anti-government "Red Shirt" demonstrations that had paralyzed the city and spawned some of Thailand's bloodiest violence in decades.

New York-based rights group Human Rights Watch says the shooting was most likely carried out by soldiers, as does a preliminary report by the government's Department of Special Investigations — Thailand's equivalent of the FBI.

But one year later, nobody has been charged in Kamolkate's death. Cases like this — and the fact that only government opponents have so far faced prosecution — have strengthened a sense that justice in Thailand is one-sided, a malleable tool favoring the Bangkok-based elite over the powerless, mostly rural poor.

"The army killed innocent people, yet one year later there have been no apologies," the 46-year-old Payao said, referring to the military crackdown that crushed the two-month protest and claimed her 25-year-old daughter's life.

"You should take responsibility for what you've done," Payao told a black-uniformed soldier outside the barracks, where she believes the troops who shot her daughter are based. "If there is no justice, I'm afraid people will have to die again."

Clutching a walkie-talkie, the soldier nodded respectfully, then bowed and walked away without saying a word.

Though life in cosmopolitan Bangkok returned to normal long ago, the societal divide between the haves and have-nots that transformed its streets into a battleground last year remains wide. Some fear the rift could spark new violence as the country heads toward July 3 elections.

The vote will be fiercely contested, and closely watched by an anxious military that has staged 18 coups in the last century, the latest in 2006 against ex-premier Thaksin Shinawatra, whose sister was named this week to head the main opposition party.

Rights groups blame both sides for stoking the crisis, which killed at least 90 people and wounded 2,000 between April and May of 2010. During those months, more than 100,000 demonstrators, mainly from the countryside, camped out in the financial district and brought the city of steep high-rises to its knees — occupying major roads and shutting down international hotels and shopping malls.

Opposition leaders had urged their supporters to turn Bangkok into a "sea of fire" — something many tried to do in widespread arson attacks after armored military vehicles finally moved in to disperse the crowds. Among the protesters were shadowy black-shirted militants armed with grenade launchers, pistols and automatic weapons.

The government says it proceeded carefully to minimize casualties as it tried to restore order, setting several deadlines for protesters to disperse. But rights groups say it used disproportionate and excessive force — including live ammunition and snipers.

And since then, "nobody on the government side has been held accountable," said Brad Adams, Asia director for Human Rights Watch.

"We've said to the government over and over again: 'If you really want to heal, you need to hold some of your officials accountable.' "

Instead, the lack of justice is driving the sides further apart, Adams said.

Prime Minister Abhisit Vejjajiva's administration has tried to heal wounds by offering compensation to victims: 400,000 baht ($13,000) payments to those who lost loved ones, lesser amounts to those injured, and lifetime monthly assistance to the disabled.

But it has also aggressively pursued opposition leaders and critics, shutting down pro-opposition radio stations and jailing hundreds — some for alleged acts of "terrorism" or insulting the nation's revered king.

"Certainly, if you ask me if there is reconciliation today, I have to say 'not yet,'" Abhisit said in a speech this month. But "the government has asserted the rule of law to show that Thailand is governed by law, and ... the work on establishing reconciliation has already begun."

To that end, the government set up the Truth for Reconciliation Commission to piece together what happened last spring. Establishing the truth is necessary before the nation can move forward, chief investigator Somchai Homlaor said. But that task has not been easy.

The commission cannot issue subpoenas or grant immunity in exchange for testimony. And Somchai said that although investigators have interviewed hundreds of people, some — particularly soldiers and some Red Shirts — were initially reluctant, suspicious of the panel's aims or fearful of prosecution.

"There must be justice first," Somchai told The Associated Press in an interview. "Otherwise reconciliation will not happen."

One problem: "the culture of impunity is very strong in Thailand," Somchai said.

The DSI investigation identified 13 cases in which security personnel may have been involved in potentially unlawful killings. The cases were transferred to police for further investigation and possible indictment three months ago, but none have been referred to courts.

Adams said he believes the government — which opponents allege ascended to power only because of military pressure on some lawmakers to defect from a previously Thaksin-allied government — "is afraid of taking on the army." The government says justice must be allowed to run its course.

The paramedic, Kamolkate, died inside Wat Pathum Wanaram, a Buddhist temple wedged between glitzy shopping malls along a street that had been occupied by demonstrators for weeks.

When the fatal volley of gunfire struck her in the thigh and back, Kamolkate was treating a mortally wounded protester. Another man who rushed to help her also was shot in the head and killed.

The DSI said green-tipped 5.56 mm bullets — used in the Thai army's M16 assault rifles — were found in the bodies of Kamolkate and at least three other people. Human Rights Watch says no arms were found in the temple.

When Payao recounts the loss, tears stream down her cheeks.

"Those who killed my daughter should be put on trial," she said. "Why is that so hard?"