Demonstrators attend a protest against rape and violence against women in Brasilia, Brazil, May 29, 2016.

© 2016 Ueslei Marcelino/Reuters

Last Sunday at 6:30 a.m., Cláudia Zerati was killed in her apartment in a building with a pool, gym, and sauna in Perdizes, an upper-middle class neighborhood in São Paulo. About 34 hours later, Siria Silva Souza was killed in a wooden shack in in Jardim Ângela, a São Paulo neighborhood of squatters without any asphalted streets or electricity.

Zerati was 42, and white. Souza was 18, and black. Zerati was a judge. The police report does not list Souza´s occupation.

And there is also Maria do Carmo Cândido, 67, a homemaker, and Celina Moura Mascarenhas Gama, 35, a lawyer. They were also killed in São Paulo on Monday.

Four women killed in two days by partners or former partners. Men who claimed that they loved them.

Those cases are not outliers, as our research shows in São Paulo and Roraima --the state with the highest rate of killings of women in Brazil, according to the latest national data. They in fact present a pretty good picture of the victims of men who think of a woman´s body as their own property: They are women of all ages, from all walks of life, and living in every corner of the country.

They are often killed with extraordinary brutality, with knives and hammers, or set afire. Killers who are police officers tend to use their guns. Abusers sometimes target the women´s family members and friends as well. And their own children. If they survive, those children will bear the imprint of those traumatic experiences for the rest of their lives.

When a woman is killed as a result of domestic violence, we have all failed. It is imperative to send people responsible for their deaths for trial and punishment. But still, could we have done something more as a society to prevent those deaths?

The answer is a resounding yes.

What starts out as seemingly small actions –trying to control what a woman does or where she goes, threats, a small push– can be first steps in a pattern of abuse that leads to death. Thousands of Brazilian women endure many episodes of violence before gathering the courage to report it. But access to justice can be an ordeal for them.

I have talked to women who walked at night to a police station after being beaten, only to be turned away, told to wait until the women’s police station opens to file a complaint. The vast majority of those specialized women’s stations are closed at nights and on weekends, when most cases of domestic violence occur.

Even at women’s police stations, some victims have to tell their stories of suffering, including sexual abuse, in open reception areas, without any privacy, exposing them to embarrassment, stigma or even more harm should their abuser learn they have talked to the police. The officers who take their statements frequently have insufficient domestic violence training. Or none at all.

And even if women are able to file a complaint, it will possibly go nowhere. A 2013 parliamentary inquiry found that in some states only a small percentage of complaints are turned into investigations, and only a small percentage of those result in charges filed against abusers. Most states did not bother providing data to the inquiry. Our research in Roraima supports the inquiry’s findings.

Thanks to a piece of 2006 legislation, known as the Maria da Penha law, women under threat can obtain a protection order, but the vast majority of those orders are still not monitored in Brazil.

Domestic violence typically escalates. That’s why, when the state misses the chance to break the cycle of violence by not responding adequately to victims calling out for help, it can be fatal. The state is failing Brazilian women and girls.

It is too late for the four women who died in São Paulo in the last few days. The best tribute to them we can offer is not to look the other way when our coworkers, our neighbors, our sisters, and our mothers suffer, and to press the authorities to open their eyes as well. And to act.