The UK foreign secretary, Dominic Raab, has been urged to draw on his experience as a former Foreign Office human rights lawyer to press the legal case that the Venezuelan government of Nicolás Maduro has systematically tortured its people.

The call was led by the prominent Venezuela human rights defender Tamara Sujú who visited London to persuade the UK to join six non-European countries in pressuring the international criminal court (ICC) to pursue a case against the Venezuelan leadership.

Raab worked as a lawyer for the FCO, including at the ICC in The Hague, from 2000 to 2006.

In theory the case could end with Maduro arraigned in front of the court, but progress with the ICC case has the potential to play into the various indirect talks currently under way between supporters of Maduro – who succeeded the leftwing Hugo Chavez as Venezuela’s president – and Juan Guaidó, the self-proclaimed interim leader recognised by most EU countries and backed by the US.

British backing for the ICC investigation would be a further blow for Maduro. The ICC referral was initially backed by Argentina, Chile, Colombia, Paraguay, Peru and Canada at the end of last year, becoming the first state referral to the ICC by other states.

The ICC launched a preliminary investigation in September 2018.

Sujú, executive director of the Casla Institute and a Guaidó supporter, said: “We need a European country, preferably Britain, with sufficiently solid institutions, a democratic tradition and commitment to human rights to join us in the ICC not just with words but to subscribe formally to the case.

“We also need Great Britain to impose personal and economic sanctions against the Maduro regime and to close their spaces.”

The Trump administration tightened economic sanctions against Maduro again this week.

Sujú has compiled more than 600 detailed cases of alleged human rights abuses. Her critics say she is part of an army of Maduro opponents who use human rights to denounce the leftwing government.

An ICC case has four initial stages, including a case to answer, identification of the victims, assessment of whether the crimes are eligible as crimes against humanity and whether the government has sought to prosecute the cases.

Sujú’s chief claim is that the arrests of demonstrators and, increasingly, of figures in the military, are systematically directed by the Maduro government, indicating the leadership would have to face justice at the ICC.

Profile Who is Nicolás Maduro? Show Political career Nicolás Maduro has ruled Venezuela without two of the greatest assets possessed by his mentor and predecessor, Hugo Chávez. He has not been lucky. And he has no charisma. Chávez enjoyed an oil bounty and sublime political talents that secured his power at home and reputation abroad. Maduro, in contrast, inherited a wobbling economy addicted to high oil prices and a system of authoritarian populism dependent on showmanship and patronage. Oil prices tumbled and Maduro proved to be a fumbling showman, exposing the financial ineptitude and ideological hollowness of the “Bolivarian revolution”. This could have doomed his presidency, which began in 2013 after Chávez died, but the former bus driver, a hulking bear of a man who rose up trade union ranks, turned out to be tenacious and ruthless. Born into a working class family in Caracas in 1962, he left school without graduating and drove buses for the Caracas metro. He became a union organiser and early supporter of Chávez, who, after leading a failed coup, led a leftwing coalition to an electoral landslide in 1998. Maduro was the speaker of the assembly before serving as Chávez’s foreign minister from 2006 to 2013, a visible if largely silent presence as the comandante held court on the world stage. Chávez anointed Maduro as his heir before succumbing to cancer. The story of his rule – and Venezuela’s agony – is a determination to keep power amid economic collapse, humanitarian disaster and international condemnation. Since January 2019 his presidency has been disputed, with Juan Guaidó being sworn in as interim president, and recognised as Venezuela’s ruler by some international powers. Crisis after crisis has buffeted his government – hyperinflation, food and medicine shortages, power blackouts, mass protests, drone attacks, defections, US-led sanctions – and Maduro has remained standing, resolute, implacable. It is a remarkable position for a man who, in a 2014 Guardian interview, described himself as a bit of a hippy and a fan of Led Zeppelin and John Lennon. “I never aspired to be president,” he said. “I always honour something that commander Chávez told us: that while we were in these posts we must be clothed in humility and understand that we are here to protect the man and woman of the streets.” Rory Carroll

“There are not random accidents of violence,” she said. “What has stood out is that they group masses of protesters 40 or 50 at the time, take them to the station and torture them as a group. We have cases where families were taken. They made the father watch as his child was tortured and then the child would watch his father be tortured. They tortured a mother and daughter, took off their clothes off before they applied electricity.”

She highlighted the death of the military captain Rafael Acosta Arévalo, who was arrested on 26 June and died three days later. At his military tribunal he was unable to stand, hear or understand what was happening and pleaded with his lawyer for help.

The UN high commissioner for human rights, Michelle Bachelet, has visited Venezuela to find political prisoners are tortured, including with electrical currents, simulated drowning, beatings and sexual violence, and is setting up a permanent mission.

