There is growing support for a dedicated Transport Police unit to be set up in Dublin.
Public transport operators have long called for more help to tackle anti-social behaviour on buses, trains and trams.
Following a string of attacks on services earlier this year, the NBRU wrote to the Transport Minister.
The union asked Shane Ross for an "immediate commitment to establish a Garda Public Transport Division".
"The mood among transport workers has changed dramatically on the back of a number of recent assaults across both our Train and Bus services", the letter said.
Fianna Fail's Dublin Spokesperson, Deputy John Lahart, agrees that the current set-up isn't good enough for passengers or staff.
He said dangerous, unruly, behaviour is "now occurring on a daily basis and have become more extreme in nature".
"The safety and security of passengers and staff must be paramount and it’s clear that to achieve that requires more comprehensive laws", he said.
Fianna Fáil is re-affirming it backing for the establishment of a dedicated unit of transport police in Dublin, to properly enforce laws across public transport services.