Morris tribunal:Donegal publican Frank McBrearty snr wrote a "plea for help" to assistant commissioner Kevin Carty in October 1998, the Morris tribunal heard.
Mr Carty is now the senior police adviser to the secretary general of the Organisation for Security and Co-operation in Europe. He was sent to Donegal in February 1999 to investigate Mr McBrearty's allegations that he was being harassed by gardaí.
In his letter, Mr McBrearty outlined how his son and nephew were wrongly identified as murder suspects following the hit-and-run death of cattle dealer Richie Barron. He also told Mr Carty that private detective Billy Flynn traced a hoax blackmail call to the home of a garda.
"Billy Flynn informs me that you are a committed member of An Garda Síochána and that I should place my trust in you. He speaks of you with great respect. My wife Rosalind and myself and my extended family have been living a nightmare for the past two years Please help us," Mr McBrearty snr wrote.
In his evidence, Mr Carty contradicted the evidence of former chief superintendent Denis Fitzpatrick, who said he consulted with him before meeting Mr McBrearty's lawyers in early 1999 to discuss prosecutions against the McBrearty family.