FARMINGTON, N.M. » Edmund Yazzie is not the type of guy you expect to see at a heavy metal concert. He is 46, well past the age of youthful angst. As a veteran lawmaker on the Navajo reservation, he is also an integral part of the establishment, known for his starched shirts, polite manner and ardent anti-marijuana stance.

Nevertheless, on a recent Saturday, Yazzie was at a metal show in this small city, standing in a throng of headbangers as a man in black roared into the microphone. But Yazzie was not there to court voters or counsel against drug use.

He was there to play.

In the small world of Navajo "Rez Metal," a cluster of rock bands that perform on and around the tribe’s reservation, Yazzie is not only a participant, but a leader, hosting concerts on his family’s ranch and touring the region with the four-man band he helped start in 2011, Testify.

Although Testify sometimes performs with other bands that have the defiant-sounding names associated with the genre – Skull Fist, Abysmal Dawn and Night Demon, for instance – the message of Testify’s songs is uplifting: Titles include "Move On" and "Live for Something, Die for Nothing."

"People have this perspective of metal: It’s going out to party, get drunk and go home," Yazzie said. "But no – for us it’s a positive thing."

Many of Testify’s fans are young Navajos grown disaffected by the reservation’s troubles: poverty, unemployment, domestic violence, Yazzie said. "They come to us for help."

While he spends his days in meetings with the 23 other delegates who make up the Navajo Nation Council, he spends his nights behind a drum set, slamming out a beat as his son Darius, 22, the frontman, growls about aching souls and native pride.

Some fans call the older Yazzie "the rocker delegate," while others call him "Pops," a nickname he rejects with a laugh. "I’m like: I’m not Grandpa, dude," he said.

The band’s formation was inspired, in part, by tragedy. In 2009 and 2010, a wave of suicides shook Yazzie’s district, and 15 young people took their lives. Two of the dead were friends of Darius. "The message is, ‘Don’t give up on life,’" the younger Yazzie said of the band. "A lot of the youth here, they don’t have that type of encouragement."

Testify is part of a larger Native American heavy metal tradition that exists on reservations around the country. Some bands, but not all, use the term Rez Metal to identify themselves.

The genre has been a dominant musical force among young people on reservations since at least the 1990s, along with rap, according to Ellen Bello, a New Yorker who founded the Native American Music Awards in 1998. She has worked extensively with Indian bands of all types and hosts an award show each year; many entries come from metal bands.

The popularity of heavy metal, Bello said, comes from its cathartic nature – making it attractive to young people in depressed regions – as well as its heavy use of drums, a mainstay in native culture. It is played at parties and concerts, while more traditional music is reserved for ceremonies.

Some metal bands preach positivity, like Testify, while others are "angry and gritty, to get a message of frustration across," Bello said.

The Navajo Nation, with some 300,000 members, has the largest Indian reservation in the United States, a region of deep canyons and towering red rock formations that is about the size of West Virginia. It is also racked by poverty, and the tribe’s government is locked in a fight over who should be its next president.

Edmund Yazzie is a former sheriff and a third-term lawmaker whose accomplishments include helping his district acquire a new health clinic. But his dedication to heavy metal is rooted in a conviction that he could have more success helping the tribe as a musician than as a legislator.

"My dream is to hit it big and make it in metal music," he said. "And I tell my people, ‘If Sammy Hagar, Van Halen or Metallica calls,’ I told them, ‘I might just have to step down.’"

On a recent concert day, the elder Yazzie spent the morning with constituents. Then he returned home, where he fed the horses.

At 4 p.m., the Yazzie family headed out for the metal show: Darius, with his spiky hair; Edmund’s wife, Raedean, 46, with her monopod and video camera; and their daughter, Kalynn, 5, toting pajamas and pink noise blockers meant to protect her eardrums.

They traveled more than 100 miles north, over red moonscapes, before arriving at Studio 18, a club at the end of a dirt road that was little more than a box heated by a wood-burning fire.

Inside, longhaired men milled about. Darius Yazzie and the two other band members, Sebastian Chaco, 29, and David Kinsel, 21, unloaded equipment.

A star-struck fan looked on. "I feel great when I listen to their music," said Aaron Bennie, 22, wearing a black Testify T-shirt. He cited his favorite song, "Codes of Honor," which celebrates Navajo men who served in World War II. "It touched me right here in my heart," he said.

Several groups took to the stage, sending musical explosions into the night. Then it was Testify’s turn.

Raedean Yazzie moved to the front, clutching her video camera. Edmund Yazzie hit the cymbals, and the band was raging, moving quickly through a five-song set – they sing in English, rather than the Navajo language. Sweat flew from the drummer’s face as his arms moved, his head rocked and his neatly combed hair became increasingly disordered.

Darius, who writes most of the band’s songs, rumbled into the microphone. "Insanity keeps on increasing," he sang. "Decide what is right. Block it out and fight the good fight."

And then as Testify wrapped up and Edmund Yazzie stepped off the stage, a man in the back scribbled his contact information onto a piece of paper destined for the band.

The man, Tim Castillo, 46, was a pastor. He wanted to invite Testify to play at his church – he thought parishioners would relate to the group’s aggressive sound and benefit from its you-can-do-it ethos.

"Our church is filled with people coming out of addiction, coming out of prison, broken homes, poverty, abuse," Castillo said. "There’s not a lot of positive."

Julie Turkewitz, New York Times