In most cases, investigations do not even lead to a trial, they said, adding that, instead, demonstrators and protest leaders are accused of vandalism or inciting public disorder.

“It’s backwards — when it’s about punishing campesinos they move fast,” said David Velazco, a human rights lawyer who has defended more than 200 rural protesters on various charges, including vandalism and disturbing the public order.

The prime minister’s office and the national prosecutor’s office did not respond to multiple requests for comment, while the Interior Ministry declined to answer questions.

The country’s current president, Dina Boluarte, who took over after Mr. Castillo was ousted, has blamed the deadly clashes on protesters who have blocked roads and attacked security forces with rocks and slingshots.

Investigations involving clashes in rural areas can be challenging, legal analysts say, partly because it can be hard to determine whether the police face a legitimate threat to their lives when they are outnumbered by protesters, said Rolando Luque, who monitors conflicts in the ombudsman’s office.