Claims that 90% of Mexican drug war victims are criminals is a statistic far removed from Cristina Roman’s experience in a country where police and military have fallen into corruption

Cristina Roman didn't know where to begin. When asked how the epic violence and criminal impunity in her native Ciudad Juarez invaded her own life, she paused, then asked: "How far should I go back?"

She decided to begin from May 2010. It was then at the height of the bloodletting there in Mexico's deadliest city when, one night at 4am, she, her husband and three sons awoke to a terrible pounding at their front door. "My husband went to see who they were. Then he said: 'Go hide with the kids. They have guns,'" she recalled.

"By the time I had my baby in my arms, the gunmen were already in the house."

Roman, 28, is a member of Mexicanos En Exilio – or "Mexicans In Exile" – a network of Mexican activists, journalists, politicos and ordinary working-class families like hers, who arrived in the United States seeking asylum from criminal assassins in Mexico. These are innocent victims of the Mexican drug war. In the words of their immigration lawyer, Carlos Spector, an immigration lawyer in El Paso, Texas, where most of these exiles end up, they "risked their lives for truth and justice in Mexico" and were "forced to leave because of the Mexican government's failure or unwillingness to protect them".

Missing persons posters in Juarez. Photograph: Daniel Hernandez

Cristina's case is different, however. She didn't protest against corruption or document violence, but fell victim for a rather banal reason: being in the wrong place at the wrong time. The incident that put her in a drug cartel's crosshairs was a mass shooting she escaped as one of few surviving witnesses. From a small home in New Mexico, where she now lives in hiding, Cristina reflected on that event, but noted it wasn't her first brush with violence in Juarez. That's how she began describing the night three gunmen broke through her front door.

Personal accounts like hers, while isolated, provide shocking glimpses of the trauma and tragedy that exist for people living amidst Mexico's brutal drug war. These stories also reveal a state of lawlessness that experts say is unlikely to stop any time soon.

As gunman entered her home, Cristina told her sons, aged eight and six, to stay calm. The men soon called for her to come out. She did, and was immediately grabbed and thrown to the floor. The men then pistol-whipped her husband, who collapsed next to her. "They asked for money, jewelry, car keys, everything they wanted," she recalled. "I said: 'I don't know what you're looking for, but you can take whatever you want. I only want my children.'"

One man – "El Vato" – hovered over her saying he would execute them all. Another gunman then said: "What are you doing? We came for him. Don't get out of control."

He said: "Go to your kids' room, close the door, and no matter what you hear, don't leave, don't speak." Cristina did as told. And for the next half hour heard them beating her husband. He groaned and wept through the assault as she huddled with their sons in silence.

After 30 minutes, when the noise finally ceased, Cristina came out to the awful realization that her husband had been kidnapped. Two hours later, her brother-in-law received a phone call with ransom instructions.

Cristina's husband owned a small used-car dealership, and over the next two days, she and her brother-in-law hustled to sell his lot, liquidate assets, raise funds, withdraw savings. "We did everything we could to get all the money together and paid half the ransom the first day, the other half the second day," she said, her voice quivering. "The third day they were supposed to return him and they didn't. The fourth day they threw his dead body in the street."

Mexican president Felipe Calderon often claims that 90% of the drug war victims are criminals. That vague sentencing of 60,000 people naturally enrages victims' families.

Nik Steinberg, a Mexico researcher for Human Rights Watch, also disputes its validity. "The government has not produced empirical evidence to back up this claim," he said. "Instead what we have found in the overwhelming majority of killings in Mexico is that the government has not even opened a criminal investigation, let alone charged or sentenced someone."

The men who killed Cristina's husband were never brought to justice. There is no way to know whether they worked for the Zetas or Sinoloa cartels, which are active in Juarez Valley. That is a strong possibility, however. According to Ben West, an analyst for geopolitical intelligence firm Stratfor, the cartels have increasingly diversified their criminal activity to include extortion, kidnapping and human trafficking, in response to losses incurred in the drug trade.

Ironically, this means that Mexican civilians are becoming victims of their government's success.

West added: "You have criminal groups taking advantage of the overall security situation and basically pulling people at gunpoint and saying give me your money. With the police all caught up in this, there is no rule of law."

Cristina took a job at a Juarez nightclub after her husband's murder. She went from stay-at-home mother to single breadwinner for three overnight, and moved in with her parents so they could help.

And for almost a year, they managed. Then the cartel violence found her again.

On 31 March, 2011, at about 8.30pm, a group of federal police officers entered the bar telling everyone to line up against the wall. Searching for weapons, they padded men between the legs, looked up women's skirts, emptied handbags and checked bathroom stalls. That level of scrutiny was unprecedented, Cristina said. At one point an officer even began groping a colleague of hers. She intervened, saying: "Hey – we respect you and your work, you should respect us. You can't treat us like that." The man backed off, but not before delivering an ominous message. "You haven't seen anything yet," he said. "The worst is yet to come."

And truly, it was.

A few minutes after the police left, two men entered the bar carrying automatic weapons. A man near entrance lunged for the doorway and they shot him. "That was the first person to go down," Cristina recalled. "I dropped to the floor. Everyone was screaming with fear."

With ruthless abandon, the assassins opened fire in every direction, killing all they could, shooting everyone in sight. "I could see people around me in pain, some people dead," Cristina recalled. At some point the men lit the bar on fire. A waitress next to Cristina ran as soon as they left, saying: "I'd rather be shot to death than burn."

"When it sounded like all the shooting had stopped, and you could smell the place was starting to burn, I had to go too," Cristina said. She ran outside, where several cars were on fire.

She ran to the parking lot and suddenly froze when four pairs of headlights turned on. They were four federal police trucks. They had never left. "The only thing I thought at that moment was: Sin Madre," she said – a phrase that literally means "motherless" but is also slang for "goddammit."

A sign wishing travellers a good trip, between Ciudad Juarez and the United States. Photograph: Daniel Hernandez

Incredibly, municipal police pulled up just then. They jumped from their cars, hurling curses at their rivals. "They turned their attention to them," Cristina said, referring to the federal police, who refused to let the responding officers through. "That's the only reason I got away."

Despite serious efforts to purge corruption from their ranks, reports of Mexican law enforcement engaged in criminal activity are rampant. "What mostly happens is police officers work by day for the city, then as a side job also do security for the cartels," said West, of Strator. "And that obviously creates all sorts of conflicts of interest."

"All levels of police are implicated," he added. "But what is probably most alarming is that the military is also falling into corruption. The government is running out of tools to fight this problem."

Cristina showed great poise escaping the El Castillo bar massacre; she fell into a daze, however, immediately afterward. "I was just wandering," she said, "lost, till 4am when I finally got back to the house."

The following day, three survivors gave statements to police about the event. Too intimidated, Cristina refused. She had no plans to talk, but that wouldn't make a difference, unfortunately. About a week later, a friend from the bar – another survivor – called Cristina to warn her that "sicarios" – assassins – were asking for them at nightclubs downtown.

Cristina had no intention of going to work at a nightclub again. "I just couldn't," she said. Nevertheless, they found her one afternoon driving on a highway. They drove a Dodge Ram, and tried to bully her toward the shoulder. They wore masks, her son said, and tried to run her off the road but somehow she pulled away.

"I'm still not sure how I managed to keep control of the car," she said. "They tried to kill me with my kids."

She stayed up that night thinking about what to do. "It had gotten to the point where I was very scared, always worried that people were looking for me," she said. "I was terrified for my children."

"I talked to my oldest son Raul about the possibility of coming to the US," she recalled. "I thought about it all night, and then on the 13 April I took my boys and what I could pack and went to the bridge."

According to the department of homeland security, 4,400 Mexican nationals have applied for US asylum in 2012. That number already exceeds the 4,000 requests filed in 2011, and is more than three times the 1,200 made in 2005, before the drug war began.

These people represent a fraction of the displaced, of course. And only a fraction of them will see their requests granted. Over the past six years, only 11% of asylum cases from Mexican nationals were granted. And that average is trending downward. As Crystal Massey, an activist in Spector's office, explained: "Unless you can show that you belong to a particular social group that is not the whole country right now, you don't qualify for asylum."

Cristina's first hearing is this fall. With federal police implicated in the massacre she witnessed, she hopes a immigration judge will find her government complicit in her persecution.

Her mother, sister, brother-in-law and nephews will go through asylum hearings too. They followed Cristina across the border after their own tragic run in with "sicarios". Gunman showed up at their door recently demanding to know Cristina's US address. Her father refused to reveal it, and for his loyalty he was taken with the promise that the rest of the family was next.

Her father was never seen again and is assumed killed. When asked for her full name and age – "Cristina Roman Dozal, 28" – Cristina offered his name too: "Manuel Roman."

And it's deaths like his, and her husband's, and the ruthless killings of innocents at the El Castillo bar that cause Cristina to grow upset when confronted by the claim that 90% of Mexican drug war victims are criminals.

"In their crossfire they're getting innocent people. In the bar where I worked, maybe they were going after one bad person, but they killed innocent people too. And then there is more bloodshed when they pursue the witnesses," she said, her voice quivering. "They go for a person, kill their mother, kill their brother. They kill lots of innocent people. They killed my father. It just keeps spreading out and it's mostly innocent people."