The Equality and Human Rights Commission is to launch a probe into disability hate crimes and harassment after figures revealed that a person appears in court every working day charged with abusing the disabled – often violently.

The formal inquiry, announced today and backed by ministers, will also investigate what public authorities – such as councils, schools, bus services and the police – are doing to protect the human rights of disabled people. It comes after a spate of high-profile cases that have seen people killed or kill themselves after suffering taunts, attacks and bullying.

Earlier this month a teenage girl was among seven people arrested on suspicion of the murder of a man with learning disabilities described by his parents as "a gentle giant". The 21-year-old had been last seen watching the television in the family home before his body was found near a local supermarket.

The commission says people with learning disabilities and mental health conditions are particularly at risk and suffered higher levels of victimisation, with low-level incidents escalating into more serious violence. The equalities watchdog has warned that any public bodies not found not to be meeting their obligations could face legal action to force them to comply with the law.

It is already investigating whether Hinckley and Bosworth council in Leicestershire is compliant with its "legal duty to eliminate disability-related harassment" after local resident Fiona Pilkington killed herself and her teenage daughter Francecca in 2007. Francecca had a mental age of four, and Pilkington was apparently driven to despair by the inaction over the abuse her family had suffered.

Mike Smith, lead commissioner for the inquiry, said reporting of the coroner's inquest into the Pilkington case last year was a "turning point for the mass media". "Before, a death of disabled person in these terrible circumstances would have got few column inches in the newspapers. But in a similar way to the tragic case of Stephen Lawrence, it was pivotal in changing the way society viewed these crimes."

Smith, a wheelchair user, has himself suffered abuse – with "Kripple" daubed over his walls in paint and wooden wedges hammered under his door to prevent it from being opened. "I did call the police, and the first five times it was like, 'What do you want us to do about it?'" But I did finally get one officer prepared to do something about it and installed a surveillance system. It shows what can happen if the collective denial is challenged."

Disabled people, says Smith, can literally become "too scared to leave home" because they are "harassed and told to ignore it by everyone else, including public bodies. It's unacceptable".

The commission says disabled people are four times more likely to be victims of crime than non-disabled people – and it has evidence that many more incidents of violence or hostility go unreported or are not dealt with properly by "social housing bodies, social services teams, crime prevention units, public transport and other public bodies in Britain".

Every working day, on average, at least one person appears in court charged with a crime against a disabled person. Nearly half of these involve violence.

Charities said the move was long overdue, and that frontline staff need training and support to deal with "disability abuse". "One of the issues, especially with hate crime, is that it is treated as a crime and not just an issue of antisocial behaviour," said Esther Foreman, a spokesperson for learning disability charity Mencap.

Maria Miller, the minister for disabled people, said: "Harassment in any form is totally unacceptable. Everyone in society has the right to live life in safety and with security. For disabled people and for those with long-term health conditions, safety and security is a right that can't be taken for granted."