The Bishop of Lancaster has led calls to protect migrant workers in the wake of the Morecambe Bay tragedy.
Police are investigating the cockle-picking trade in Morecambe
The Right Reverend Patrick O'Donoghue told Radio 4's Today the government had to address "rogue gangmasters".
The bishop added his voice to calls by MPs for the licensing of migrant recruitment by gangmasters.
The Rural Affairs Select Committee last year said it was "appalled" by the inadequacy of government efforts to tackle the problem.
Nineteen people, mostly Chinese, drowned while picking cockles in Morecambe Bay on Thursday night.
Labour MP Jim Sheridan recently introduced a bill to licence gangmasters in a bid to ensure they meet basic employment standards.
In a letter to the Guardian last month Mr Sheridan said: "The modern-day faith in labour market deregulation means many employers can, and often do, operate without regard to the law.
"Weak voluntary codes offer no protection from illegal hours, low pay or intimidation, and the authorities do not have the means to keep track of gangmasters' activities."
Agricultural work is often only loosely regulated
Father O'Donoghue, the chief of migration policy for the Catholic Church, called Mr Sheridan's proposals "crucial".
"Too many reports of abuses of health and safety, exploitation and criminal acts of intimidation by unscrupulous gangmasters have surfaced," he said.
He told Today voluntary codes were insufficient and the government needed to set-up legislation.
Don Pollard from the TGWU told the programme: "Everybody on the legitimate side in the industry supports the registration of gangmasters."
But he said there seemed to be "reluctance on the part of different government ministries" to support the private member's bill.
Last September a Commons Environment, Food and Rural Affairs Select Committee report painted a bleak picture of conditions for migrants working in the unregulated "black economy".
The report said gangmasters create "a culture of fear" and often neglect workers' safety and general welfare.
A Cambridgeshire Citizens Advice Bureau told the committee migrant farm workers were being housed in partitioned containers, without running water, and were forced to pay back £100 to their employers if they left their jobs.
In July 2003, three migrants travelling to pick spring onions died when their van - reportedly driven by a man who could not understand English - passed a warning sign at a level crossing and was struck by a train.
The committee blamed the pressure put on farmers by supermarkets for "creating an environment where illegal activity by gangmasters can take root".
But it warned that government inaction had exacerbated the problem.
"No government department appeared willing to take any responsibility for addressing the difficulties," the report claimed.
And it called Operation Gangmaster, set-up five years ago to address the problem, "a woefully inadequate response".
The committee called for a full policy review and "a more interventionist approach" to regulating casual labour.
But a spokesman for the Home Office said it was tackling the problem, primarily by opening legal access routes for regulated economic migration and clamping down on the illegal workforce.
On Saturday the Minister for Work and Pensions, Chris Pond, told Today the government had gone a long way in developing a voluntary code for work providers.
But he admitted the government needed to consider whether introducing another tier of law would do much to regulate their activities.
He said: "While licensing and registration is something that we are very seriously considering, we must not pretend that that's going to be a panacea."
The TUC says legal protections for migrant workers in Britain are "wholly inadequate" and enforcement was directed too much at workers rather than employers.
A TUC report warned: "Those who may not have official entitlement to work are often amongst the most oppressively exploited."
The Department for Environment, Food and Rural Affairs has concluded gangmasters can be the only "realistic source" of casual labour for some farmers.
It is currently looking at a code of conduct for gangmasters, to make it easier for farmers to ensure recruiters operate within the law.