Jin Sato, the mayor of the destroyed town of Minamisanriku, has been accused of making decisions that were irresponsible rather than heroic. (David Guttenfelder/AP)

On a Friday in March three years ago, as a tsunami barreled in, the emergency workers in this coastal town stayed at their posts in a three-story building on low ground, never receiving an evacuation order. They hurried to the rooftop at the last moment, but even there they were submerged in the furious brown churn. When the wave pulled back, 10 of the 44 workers remained.

“Everybody was speechless,” said Tokunori Sato, one of the survivors. “Most of the people were washed away in one wave.”

The town workers in Minamisanriku have became a poignant source of national pride in Japan, their sacrifice already highlighted in some school textbooks. But in Minamisanriku itself, that narrative is under siege. A painful debate is underway about the decisions made by the mayor that day and particularly whether emergency workers should have been evacuated — as advised by the town’s disaster protocol — along with other citizens.

Conventional thinking casts Japan’s mega-tsunami as an unpreventable tragedy, but disasters, viewed up close, are rarely clear-cut, composed of so many small decisions that spare or cost lives. The dispute in this town — in which a former mayor has turned against the current one — speaks to the nature of disaster aftermaths and the sometimes-complicated process of determining whether death was preventable.

In some calamities, such as the 2010 oil spill in the Gulf of Mexico or the sinking of a South Korean ferry in April, the guilty parties are easy to pinpoint. But in Japan, the earthquake and tsunami of March 11, 2011, left behind a more ambiguous search for blame and absolution, one that persists even as the region tries to rebuild.

Questions about the Minamisanriku mayor’s decisions emerged soon after the tsunami. The case is especially charged because it involves two of the town’s most prominent men, both of whom say they are devastated by the tragedy.

Spurred by a criminal complaint lodged by former mayor Shun Makino, police are looking at whether Mayor Jin Sato should be prosecuted for criminal negligence for his handling of the town’s emergency staff. If police find grounds for a case, Sato could stand trial for his actions on a day when more than 15,000 people were killed along Japan’s northeastern coast.

Sato, 62, is a rooftop survivor, and his tale — of clinging to a fire escape staircase, of gasping for breath as the wave crested and fell — was extolled in news media accounts in the weeks after the tsunami. Sato narrowly won reelection last year, but some in the town — Makino, most vocally — have come to see Sato’s decisions as irresponsible rather than heroic, and they resist the narrative that the workers’ sacrifice was unavoidable.

Makino’s son, Noritaka, was among Sato’s employees. His body was found a year and a half after the tsunami, partially buried on an uninhabited island three miles away.

“We were all aware a super-high tsunami was coming,” Makino said. “If it was only the mayor going to the rooftop, that’s okay. But why didn’t he tell others to run away?”

A monster wave

Makino says Minamisanriku’s emergency workers should have fled the disaster prevention center — their headquarters — well before the tsunami struck. They had 32 minutes between the 9.0-magnitude earthquake and the first wave. Higher ground was only a couple of hundred feet away. The town’s disaster code advised that all townspeople, in the event of water levels forecasted at 10 feet or higher, evacuate to a building of at least four stories. Sato had helped draft the code.

Sato, though, says he and his workers had no choice but to stay in the three-story building. Each person at the disaster center had a pressing duty: closing floodgates at the waterfront, contacting officials in charge of setting up evacuation centers, making announcements on a public-address system wired throughout the town. “Head to higher ground!” two of Sato’s employees wailed for most of the 32 minutes before the wave struck. When Sato saw water surging into a nearby riverbed — the first sign of the tsunami — there was no time to run. He and his employees dashed to the rooftop, and he thought they might be safe.

The rooftop was 39 feet above ground. Japan’s meteorological agency was forecasting a 33-foot wave, and 18-foot sea walls at the town’s coastline might mitigate the surge.

Instead, the wave was a monster: 79 feet at its highest point. Minamisanriku’s low-lying downtown was pulverized.

“People who intend to make a case against me say, ‘You should have known something bigger could come.’ But I’m not a god with superpowers,” Sato said.

Minamisanriku was not the only town along Japan’s shoreline to lose many civil servants in the disaster. And the frantic work by city employees in the minutes before the tsunami hit almost certainly saved lives. The tsunami damaged or destroyed more than 60 percent of the town’s buildings, but by the time it struck, the majority of townspeople had scurried to the surrounding hills. Most of the 548 who died in Minamisanriku were elderly or immobile.

Sato says he is proud of his employees. The town evacuation rules apply to civil servants, he says, but they must first perform their duties.

“If the city hall members all ran away to save their own lives, more townspeople would have died,” Sato said.

Questions of preparedness

Minamisanriku had long prepared for a major tsunami. After an 18-foot tsunami in 1960 — in which Sato lost his boyhood home — town officials built the sea wall and began conducting annual disaster drills.

But Makino says Sato failed to carry out an important safety pledge.

Minamisanriku was created in 2005 from two shrinking municipalities: Utatsu, a village of fishermen and farmers, and Shizugawa, a more bustling area of shops and commerce. At the time of the merger, Makino was mayor of Utatsu, and Sato was mayor of Shizugawa. Makino, who was ready to retire, did not run for mayor of Minamisanriku. But assembly members in his village made a demand. They stipulated that the newly formed town move its city hall and disaster prevention center out of low-lying Shizugawa and onto higher ground.

Shizugawa’s assembly members agreed.

With Sato as mayor of Minamisanriku, however, progress on relocation was slow. Meetings were held and committees formed, but the relocation was, at best, a far-off ambition. Makino says Sato was “buying time,” concerned that an exodus of civil servants from downtown would hurt shops and restaurants. Sato, in a letter to Makino and 16 other bereaved family members after the tsunami, said the relocation was held up because of “financial issues” and local opposition.

Makino also takes issue with another aspect of Minamisanriku’s preparedness. The town’s portable telecommunication devices, which could have freed workers from staying at the disaster center to broadcast their warnings, were not on hand the day of the tsunami because they were stored in a nearby gym.

Makino sometimes looks at a series of photos snapped from higher ground minutes before the tsunami struck. They show dozens of helmeted civil servants huddled on the rooftop. In a subsequent photo, the entire building is underwater, except for a radio antenna to which one worker is clinging.

If the building had been in a different place, Makino said, “it could have been a different story.”

On message boards and blogs, some say the mayor should not be held accountable for the toll of a tsunami of such great magnitude. Others sympathize with Makino.

Another family joined Makino’s criminal complaint but then withdrew. Miyoko Chiba, a friend of Makino’s whose son-in-law was killed at the disaster center, says some grieving relatives — even those who take issue with Sato’s decisions — are “mentally stressed and do not want to get into a difficult situation.”

Makino, 75, with the stout bearing of an old boxing trainer, puts it differently.

“Not everybody has the guts to do this,” he said.

Painful memories

Makino and Sato rarely dealt with each other when they were mayors of abutting towns, and since the tsunami, their only contact has come in a series of letters in which Makino and others pressed Sato on his preparedness. (Sato replied, defending himself.) When Sato and a deputy were making door-to-door visits paying condolences to those who lost loved ones in the tsunami, Makino — notified ahead of time — told them not to come.

“It’s too late,” he said.

Neither man says he has any indication of what the police investigation will determine, and the authorities handling the case declined to comment.

Both men endure pain the case won’t necessarily resolve. At his rebuilt home on a hilltop, Makino maintains an altar with photos of his son, who had a wife and three children.

Sato, meanwhile, works out of a temporary office — one built on higher ground. The old disaster center is one of the last two downtown buildings still in existence. It is a skeleton of rusted beams, everything else flushed out, including the iron rooftop fence that most workers clung to as the wave washed in.

“I drive by that building every day,” Sato said. “I think about what happened there every day.”

Yuki Oda contributed to this report.