Nearly 100 MPs - many of them Tory backbenchers - voted today to give ministers rather than judges the final say over whether deportation would breach the human rights of foreign criminals.
Tory MP Dominic Raab's amendment to the Immigration Bill was defeated by 241 votes to 97, Government majority 144.
The amendment only failed thanks to opposition from Labour and Liberal Democrat MPs. Downing Street, anticipating a massive rebellion, decided to order Tory ministers to abstain so as not to lose face.
During the debate, Mr Raab said foreign criminals were using their right to a family life as the "joker" to escape deportation.
The MP for Esher and Walton said many crime victims were being put at risk because their attacker remained in the UK, as he told the Commons that human rights had become "dirty words".
He said it was time the law was changed so foreign criminals could no longer use Article 8 of the European Convention on Human Rights - a right to a family life - to escape deportation.
The House of Commons heard that a Freedom of Information request from the MP had found there were up to 400 cases each year where foreign criminals used Article 8 to avoid being sent to their home country, while 89% of all successful appeals to remain in the UK relied on criminals basing their claim on a right to a family life.
Under the Immigration Bill, the Government wants to oblige judges to take in to account factors in favour of deporting a criminal.
But Mr Raab says this change would still mean too much discretion for judges to allow those who want to stay in the UK to claim a right to a family life.
He has tabled an amendment to the Bill - supported by 105 other MPs - which would give the Home Secretary the decision in any case. The only route left to a foreign criminal after a decision taken by the Home Secretary would be in the High Court.
Today, Mr Raab told the House of Commons the victims of crime wanted foreign criminals deported.
He said: "You really do actually have to study the case law of the Immigration Tribunal to appreciate the extent to which these cases walk the moral balance of British justice, endanger the public and frankly, for many people outside of parliament, make human rights dirty words. That is something I deeply regret.
"Some argue the rights of the partners and children of serious convicted criminals must be given due weight. But in reality, and this is the crucial point, Article 8 is being expanded to protect the criminals' rights and not their families. Far from safeguarding the vulnerable, it can expose them to undue pressure, if not worse, by dangerous offenders."
He added: "My amendment is different from (the Government's proposal) because it is mandatory. Serious offenders cannot use Article 8 as the joker to wheel, pull out, trump deportation.
"Unless there is a tangible threat to life or limb, these convicted killers, rapists, drug-dealers and other very serious criminals should be sent home. They should not stay on the streets of Britain."
Earlier, there was confusion in the Commons as Home Secretary Theresa May sought to attack Mr Raab's amendment just as Downing Street was ordering ministers to abstain in the vote.
She told MPs that Mr Raab's amendment was "incompatible" with the European Convention on Human Rights.