The RSPCA should be stripped of its power to prosecute in animal welfare cases because there is a 'conflict of interest', a Commons select committee has been told.
The Environment, Food and Rural Affairs Committee questioned whether it was appropriate for the charity to bring forward prosecutions while being involved in campaigning and fundraising for the issue.
They called on ministers to change the law so the RSPCA could continue their welfare work, but hand over criminal charges to the Crown Prosecution Service.
But the RSPCA defended its work and said the move was not supported by the government or animal welfare groups.
The charity has also heavily committed itself to livestock cases. For example, an appeal for information was issued by the RSPCA after six sheep were attacked by dogs in Berkshire, and a Bedfordshire man has been disqualified from keeping livestock for life after 100 cows were found in distressing conditions, due to the investigations conducted by the RSPCA.
David Bowles, head of public affairs at the RSPCA, told Sky News: "If you hand it over to the CPS - of course they will have other more important high-profile things; murders, rapes, those sorts of things.
"You'd expect them to take priority over animal cases - my fear is that animals will go to the bottom of the list."
'Not convinced'
Committee chair Neil Parish said the RSPCA does important work investigating animal welfare cases.
"I would like to see its dedicated and professional staff continue that vital work. The committee is not convinced, however, that the RSPCA is in a better position than the Crown Prosecution Service when it comes to prosecuting animal welfare cases.
"It should step back from making prosecutions itself, continuing instead to work closely with the police and prosecution service to protect the welfare of animals."
Sir Edward Garnier, a former Conservative Solicitor general, told the Telegraph: "It would be much safer if we have a clean break and put the prosecutions in the hands of the CPS, rather than in the RSPCA. If it requires legislation then the government should introduce the legislation as soon as possible."
In Scotland and Northern Ireland, animal welfare groups have the power to investigate cases, but the decision to prosecute lies with the state.
Opposing committee members stressed that anyone had a right to bring forward a private prosecution and "to single out the RSPCA as not being able to do this would be invidious, as it has the experience and skills and it furthers its charitable objectives".
The RSPCA prosecuted the Heythrop Hunt, former prime minister David Cameron's local hunt, at the end of 2012 with success only coming after huge sums were spent.
'Proud of our 92% success rate'
RSPCA chief executive Jeremy Cooper rejected the MPs' criticism: "We are extremely proud of our near 200 years of experience investigating and prosecuting animal cruelty and our 92% success rate - which is currently a higher percentage than the CPS. For us the key test will be if the recommendation improves animal welfare and we suspect the answer in this case would probably be no."
"Our research shows that 89% of the general public back our prosecutions work and they will be confused why a small number of MPs would suggest stopping the RSPCA carrying out a role which we are very good at and which is paid for by public donations rather than out of taxes.
"This recommendation is not supported by the Government, vets, other major animal welfare charities and local authorities, and flies in the face of the majority of evidence put before the committee. We will consider this report carefully while we will continue to prosecute those who starve, beat, stab, burn and abuse animals."
