A provision in the home secretary’s Nationality and Borders Bill, which is at the committee stage, could give officials legal protections if a refugee dies in the English Channel.
Last month, the Home Office said that it was training Border Force guards on jet-skis to push back small boats from the shores of the UK.
It is understood that guards are at risk of prosecution if a migrant is injured or drowns under existing laws.
Immigration barrister and author Colin Yeo highlights a section of the Bill that states an officer is “not liable in any criminal or civil proceedings” for actions carried out during a pushback operation at sea.
This is providing that the act was done in “good faith” and with “reasonable grounds” for doing so, the Bill states.
On his website Freedom of Movement, Mr Yeo claims this could “make officials immune from criminal and civil court action if a refugee dies during a marine pushback operation.”
However, he stressed that the clause is unlikely to provide a legitimate defence, arguing that if a border official did not rescue a refugee in distress they would be breaking both international and British law.
The family of someone who died in such a way would be able to file for compensation under human rights law, he adds.
His warnings come as Ms Patel is under pressure from her party to reduce numbers of migrants entering the UK via small boats.
Over the course of two days last week, more than 1,000 people in at least 40 boats made the crossing after a period of bad weather had calmed.
Since the start of the year, more than 17,000 people have made the dangerous crossing – more than double the number in 2020.
More than 25,000 people have risked death crossing to the UK aboard dinghies, kayaks and other small boats since the beginning of 2020, PA news agency data shows.
Despite the sharp rise in the number of boats arriving on the south coast, asylum applications in the UK fell in 2020 to 29,456 – significantly lower than the 93,475 asylum applications made in France and the 121,955 made in Germany.
The Bill means that anyone arriving in the UK via an illegal route, such as by a small boat, could have their claim ruled inadmissible, receive a prison sentence of up to four years, have no recourse to public funds, and could have their family members barred from joining them in the country.
Labour has tried to block the legislation, but noted that it acknowledges the need to address the increasing number of “dangerous” boat crossings.
Four barristers led by the human rights QC Raza Husain claim that the Bill “represents the biggest legal assault on international refugee law ever seen in the UK.”
Home Office sources have suggested they are seeking to protect Border Force guards from prosecution, and that the provision in the Bill complies with all international obligations.
A Home Office spokesperson said: “As part of our ongoing response to these dangerous crossings, we continue to evaluate and test a range of safe and legal options for stopping small boats.
“All operational procedures used at sea comply and are delivered in accordance with domestic and international law.
“We will fix the broken asylum system through our new plan for immigration, break the business model of people smugglers who put lives at risk and welcome people through safe and legal route.”