Ministers have denied fears measures intended to cut red tape could give them wide-ranging powers to change laws without needing Parliament's approval.
The laws are designed at cutting red tape
Cambridge University law experts say the Legislative and Regulatory Reform Bill would give ministers the power to do things such as scrap jury trials.
For the Tories Ken Clarke said it could "sweep away parliamentary procedure and debate on an astonishing scale".
But minister Jim Murphy insisted the bill would have safeguards built in.
He told BBC Radio 4's Today programme he is thinking of giving House of Commons committees a legal veto over any proposals.
The bill is intended to allow ministers to axe uncontroversial "red tape" without the time-consuming need for full parliamentary scrutiny.
Mr Clarke, chairman of the Conservatives' democracy task force, said legislation was needed to tackle red tape but said there needed to be explicit safeguards, not just verbal promises from ministers.
Law experts at Cambridge University have also voiced concern about the potential impact of the bill.
The Cambridge University academics, headed by Professor John Spencer QC, warned in a letter to The Times newspaper: "If passed, the government could rewrite almost any act and, in some cases, enact new laws that at present only Parliament can make."
In its current form, the planned new law could allow the government to curtail or abolish jury trial, place people under house arrest, rewrite immigration laws or sack judges, they said.
Mr Murphy told Today that previous legislation to streamline the burden of regulation had not worked.
The government was taking action to ensure the UK remained competitive, he said.
"I have given assurances that there are more safeguards on the face of this bill than before, that we will have statutory consultation, we will not do anything that is highly controversial and the relevant select committees of the House of Commons will have a veto on every single proposal," he said.
Mr Murphy said he would look at making the veto plan part of the legislation.