There is a Mathias Kerrigan in Cloughbrack, who had several children within the timeframe you are suggesting, that was involved as an informant to the 1882 (or 1883, depending on what you read) murder of a father/son bailiff team that was coming to evict tenant farmers from their land on behalf of Lord Adrilaun (Guinness family heir). Kerrigan was a farmer on one of the properties. My familial line was also involved (the Higgins), and several of them were prosecuted and hung. If this is the correct Mathias Kerrigan - which it sounds like it might be - getting information may prove a bit tricky, as documentation for Irish tenant farmers can be sparse. There is a fair amount of information on this part of the history however. If you were to look up "Huddy murders" that would be a good space to start. That side of my family has been able to track a good portion of information due to solid family lore being orally passed down, and then a cousin marrying a geneologist who has been researching and compiling information for a book since 1993. Even he said he occasionally ran into to dead ends for a lot of different reasons relating to documentation and Irish Catholics who did not have great wealth.