The family of a Seattle-area resident being held prisoner in Mexico is pleading for the US State Department to intervene and help secure her release.

Nestora Salgado has been detained in a Mexican federal prison for 18 months, allegedly for attempting to end political corruption in her hometown of Olinala, in the Mexican state of Guerrero, according to her supporters. Salgado was arrested just one year before political corruption in Guerrero came under scrutiny after 43 college students were kidnapped and "disappeared" in the town of Iguala in September 2014.

Salgado, 42, is a naturalized US citizen who lived in the US for more than 20 years with her husband and daughters in Renton, a suburb south of Seattle. Su Docekal, the leader of the Freedom for Nestora Committee, told VICE News that Salgado began to regularly visit her hometown of Olinala in Mexico in 2004, bringing clothes and toys to her impoverished neighbors.

In 2013, Salgado and her neighbors in Olinala decided to ramp up the efforts of a local community police group in response to growing violence and lack of police presence in the town. Under Mexican federal law, indigenous people are allowed to form their own civilian police forces, Docekal said, explaining the group elected leaders and held regular assembly votes on issues that affected their town. After Salgado was elected leader of the group, Docekal said Guerrero's governor gave them uniforms and vehicles.

'The problem is that the townspeople could see that the politicians were collaborating with the cartels instead of stopping them.'

"The problem is that the townspeople could see that the politicians were collaborating with the cartels instead of stopping them," Docekal said.

Jonathan Fox, a professor at American University's School of International Service, has been following the case closely. His academic research has focused on the political landscape of Guerrero and the community police groups across the region. He said corruption is endemic in Guerrero.

"One of the reasons community police evolved in first place was when criminals were captured they were immediately released because they had friends in high places," Fox said. "So there was understandable skepticism on the part of the community police about what would happen to criminals when turned over to conventional authority."

Though she remained a US resident, Salgado stayed temporarily in Mexico to lead the community police, Docekal said. Fox said it is not unusual for Mexican-born US citizens to return to Mexico to help their native communities. "There's a tradition of Mexican immigrants going back to their hometowns, though they may be very settled in the US. It is considered about loyalty to one's hometown," Fox said.

When the town sheriff in Olinala was allegedly caught destroying evidence and taking livestock from a crime scene, Salgado and other volunteers arrested him and said he should stand trial.

"The community police were going after the partnership between organized crime and local politics, trying to break the partnership," Fox said.

The day after she arrested the sheriff, Salgado was arrested by federal police and flown by private plane to a maximum-security federal prison. She was charged with kidnapping the sheriff and others arrested by the community police, Docekal said. According to Docekal, Salgado is still waiting for her trial date to be set.

Fox said civic institutions in Guerrero have failed to serve their communities, and that citizens have been creating their own police forces for years in the region. Salgado, he said, seemed to be in jail "for having tried to get the bad guys."

"Basically, the people who should be in jail are influential enough to keep these people [like Salgado] in jail, " he said.

Jose Luis Avila, Salgado's husband, told Seattle's KIRO news station that his wife was working for justice and should be freed.

"If you do something that is wrong you should be killed or end up in prison," he told the station. "But when you are working for something that's right, under the law you know, and the next day you are in a maximum security prison, it's really hard."

Avila could not be reached by VICE News for comment. He and his daughters are part of the Freedom for Nestora committee headed by Docekal, who said Salgado is struggling to maintain her health in poor prison conditions. She has neuropathy, a type of nerve damage that causes chronic pain.

A federal judge in Mexico refused to uphold the federal charges against Salgado and recommended that the state courts also drop the charge of kidnapping, but the state court has not yet responded, Docekal said. Rogelio Ortega, the newly appointed interim governor of Guerrero, has said Salgado should be released, but he has had no traction in steps toward actually freeing her. The previous governor, Angel Aguirre, stepped down after the disappearance of the students in Iguala.

"They tried to bring federal charges against her as well but federal judge said it was ridiculous, said she was performing her legal duties as the elected leader of the community police," Doceckal said.

Docekal and Salgado's family and supporters have urged local, state, and federal politicians to intervene in Salgado's case, as well as the UN. So far, only Salgado's local Congressman in Seattle, Representative Adam Smith, has taken up the issue, Docekal said. The State Department did not respond to a request for comment from VICE News.

"She is a US citizen and they really need to be doing more on her behalf," Docekal said. "She's being held completely illegally."

Fox said the case is indicative of similar problems that plague Guerrero and other parts of Mexico.

"The underlying crisis of law there is impunity," Fox said. "That the actual criminals are rarely successfully prosecuted for crimes, and the irony in this case is it's one person who is really willing to stick their neck out and take on the problem is now a criminal. The pursuant of justice has been criminalized."