The Garda Representative Association (GRA) says calls for a public inquiry into the Jobstown case are 'farcical'.
Earlier, Solidarity TD Paul Murphy said a campaign for an independent inquiry into the case will now be 'stepped up'.
Deputy Murphy and five others were found not guilty of falsely imprisoning the former Tánaiste Joan Burton and her adviser Karen O’Connell at a water charge protest in 2014.
Last night, the Taoiseach said the Garda Commissioner Noirin O'Sullivan and her senior management should "look into" the evidence given by members of the force in the Jobstown trial.
Speaking on RTÉ Prime Time, Leo Varadkar said: "We need to be able to trust that when the gardaí stand up in court and they say something happened that it did happen - and it shouldn't conflict with video evidence and if it does then that is a problem."
The remarks were followed by confirmation that gardaí have begun an internal review into their handling of the Jobstown case.
An assistant commissioner is leading the inquiry, which was set up the day after the Jobstown trial concluded.
Deputy Murphy is welcoming the Taoiseach's comments, which he describes as "significant".
He argued: "It's some level at least of implicit admission that something seriously wrong may have been happening in this case."
However, he added that the comments need to be followed up on.
"The idea of gardaí investigating gardaí is clearly not a very sensible way to go about investigating it - so we will be stepping up our calls for an independent and public inquiry," he suggested.
Speaking on Newstalk Breakfast, John O'Keeffe from the GRA said he is 'flabbergasted' at calls for a public inquiry.
Saying the calls are 'farcical', he observed: "I believe Mr Murphy probably shouldn't be content to waste millions of taxpayers hard-earned money on a case that seems to be all about his political cause and agenda, rather than some noble fight for truth or justice.
"The Taoiseach was more circumspect, but even he seems to be part of this bandwagon that's just rolling and rolling and rolling - that the frontline Gardaí are the state 'bully boys'. Nothing could be further from the truth."
He said any concerns about evidence should be lodged with a local Garda station, the Garda Internal Affairs department or the Garda Ombudsman (GSOC).
He said his organisation is calling for body cameras for guards, arguing: "These are the things that will give us justice for all - for gardaí, for the general public, and for Mr Murphy."
