TDs are elected to make the laws, not to interfere with them, or our justice system.
Whatever the motives that encouraged him to do it, I have absolutely no sympathy for Trevor Sargent who rightly resigned his junior ministerial job after this newspaper revealed he'd tried to stop a garda prosecution.
An inexperienced garda might have been intimidated if he had received a letter from a junior minister, on department-headed notepaper, saying it was shocking and inappropriate to proceed with a prosecution against one of his constituents.
Thankfully, the garda who Trevor Sargent wrote to ignored the appeal and carried out their job.
It is now time for our TDs to call halt to the type of clientelism that is giving the political system a bad name. We all know that people use their TDs' clinics to appeal for everything from medical cards to new schools.
But TDs should have absolutely no role in trying to influence the course of justice on behalf of constituents.
They should learn from mistakes of the recent past, not all confined to any one political party either.
In 2002, Progressive Democrat junior minister Bobby Molloy resigned after it emerged he intervened in the case of a serial rapist found guilty in October 2001. While he was awaiting sentence, an official in Bobby Molloy's office made a phone call to the judge enquiring about correspondence from the rapist's sister.
In 2007, the constituency office of Fianna Fail junior minister Tony Killeen made representations to secure the early release of a convicted murderer who was jailed in December 1992 for the murder of a man in a Clare pub.
And in April 2008, Cork Labour TD Kathleen Lynch was involved in a controversy where she wrote a letter testifying to the good character of the parents of a man accused of raping two teenage sisters. The man was convicted and sentenced for 13 years.
Sargent last night tried to defend his role by suggesting he was intervening on behalf of a responsible citizen who was seeking to prevent some anti-social behaviour. But to listen to one constituent's version of events and dictate to the gardai how they should proceed, or not, with the prosecution on the basis of what he was told is as blatant an abuse of ministerial office as you could possibly get.
The only thing to Trevor's credit in this matter is the fact he immediately admitted he was wrong and resigned within hours of the story breaking in this newspaper, unlike some recent protracted political resignations.
Let our politicians learn a lesson and use this latest case as a turning point. We all know people use their TDs as their fixers. Their weekly clinics are packed with people lobbying for all sorts -- new school buildings, better water supplies, planning applications, and the grant for the local GAA or soccer club.
For better or for worse, it is this kind of accessibility that is the bread and butter of our political system. It may be flawed but until it is changed, woe betide the TD who believes he or she can survive without looking after the parish pump.
But when political clinics stray into territory such as crime and the justice system there is a problem. Leave the gardai to police, the judges to adjudicate. And if TDs don't like what happens in our garda stations or in our courts etc, then they should go into the Dail and help legislate for change.