Internet bullying was believed to be a factor in Donegal schoolgirl Erin Gallagher taking her own life last October at the age of just 13.
Internet abuse is being cited as a factor in the death of Fine Gael junior minister Shane McEntee, who took his own life before Christmas after he was subjected to a torrent of abuse after the Budget.
The abortion debate has also resulted in cyber attacks. It was suggested on Twitter that anti-abortion campaigner Senator Ronan Mullen be "crucified with rusty nails".
The Government has asked the Oireachtas Committee on Transport and Communication to investigate cyber-bullying and draw up a report that will recommend new legislation.
But many who work to combat social-media bullying say legislation is already in place but is just not being used by gardai, victims or families.
Online security expert Paul C Dwyer, president of the International Cyber Threat Task Force, cited the Non-Fatal Offences Against the Person Act. "There needs to be a public awareness campaign to drive home the fact that what is illegal offline is illegal online," he said.