Conservative MP Ann Widdecombe is calling on the government to tighten up the laws governing hunting with dogs.
Ms Widdecome says the hunting ban is too lenient
Hunt supporters claim thousands of people turned out at 250 Boxing Day hunts to show their opposition to the hunting ban in England and Wales.
The hunts claim they are acting within the law and the RSPCA said many had switched to drag and trail hunts, using fake scents.
But some anti-hunt groups say foxes are still being chased illegally by hounds.
Under the 2005 Hunting Act packs of dogs are no longer allowed to be used to chase down wild foxes.
Instead they are supposed to use techniques such as drag hunting, where dogs follow a trail laid in advance by a runner or rider dragging a lure.
But there have been claims that police lack sufficient powers to investigate whether hunt supporters are keeping within these new rules.
Ms Widdecombe, who supported the hunting ban, said the original legislation had been too lenient and needed to be re-thought.
"The reason that it hasn't been effective is because in many ways we were far too kind in order not to accidentally get other activities like falconry, caught up in it. We left too many loopholes."
She said no-one was proposing looking at the whole law again.
"But to look at the extra powers that the police have asked for and to look at tightening some loopholes," she added.
Simon Hart, chief executive of the Countryside Alliance, which has campaigned to keep hunting, said: "Quite simply the Hunting Act isn't working.
"It is a bad law riddled with inconsistencies, and its effects are entirely negative.
He added that it was "discriminatory piece of legislation" which did nothing for animal welfare.
The Alliance has also commissioned a poll which showed only a third of people thought the new legislation was working.
The League Against Cruel Sports, which monitors hunts, says up to 40% are breaking the law.
'Obey the law'
But the league's head of public affairs, Mike Hobday, also said Boxing Day hunt numbers were boosted by those supportive of the new rules.
He said there were reports of people saying they would not have turned out if the hunt had been chasing foxes.
There was no "mood amongst the public to think that chasing and abusing animals for entertainment is acceptable for a modern society", he added.
However, it blames Countryside Alliance members for "a catalogue of misdemeanours" involving a "disturbing level of abuse, intimidation and trespass" since the first hunting season to follow the Hunting Act began on 5 November.
"Just as the Theft Act did not stop burglary, the Hunting Act cannot stop cruelty - what is needed is for people to obey the law," Mr Hobday told BBC News.