Legislation governing the smacking of children needs to be relaxed so working-class parents can instil discipline in their homes without fear of prosecution, a senior Labour politician has said.

The Tottenham MP David Lammy claimed that Labour's 2004 decision to tighten up the smacking law was partly to blame for last summer's riots, which erupted in his north London constituency.

In an interview with LBC Radio, the former education minister said: "Many of my constituents came up to me after the riots and blamed the Labour government, saying: 'You guys stopped us being able to smack our children.'

"I have to say when this was first raised with me I was pretty disparaging. But I started to listen. These parents are scared to smack their children and paranoid that social workers will get involved and take their children away."

Lammy, who admitted to smacking his three- and five-year-old sons, said working-class parents should be able to physically discipline their children to prevent them from joining gangs and getting involved in knife crime.

Current legislation, enforced under the Children Act 2004, says parents are allowed to smack their offspring without causing the "reddening of the skin".

Previously they could use "reasonable chastisement", with a judge deciding whether they had overstepped the mark. However, since the 2004 amendments the decision has been left to social workers.

Lammy said a lot of parents in his constituency had been left confused by the changes and were reluctant to physically discipline their children in case they were contacted by social workers.

He added: "The law used to allow 'reasonable chastisement', but current legislation stops actions that lead to a reddening of the skin – which for a lot of my non-white residents isn't really an issue."

The politician said parents in Tottenham had to raise their children "with knives, gangs and the dangers of violent crime just outside the window", but "no longer feel sovereign in their own homes" because of the laws.

"The ability to exercise their own judgment in relation to discipline and reasonable chastisement has been taken away," he said.

Lammy has set out his support for changing the smacking laws in his book, Out of the Ashes: After the Riots.