Requests were sent to 60 countries or territories in 2020.
The number of times Ireland looked for help from other countries in solving crimes increased by nearly 27 per cent last year.
85 requests were made to the US relating to child pornography offences.
Eoghan Murphy reports:
"Under Mutual Legal Assistance legislation, Ireland can look for help from other countries in criminal investigations or proceedings.
The gardaí may want to ask foreign police to interview witnesses or seize a piece of evidence.
The Director of Public Prosecutions says this legislation was used 815 times by the state last year - compared to 643 in 2019.
Requests were sent to 60 countries or territories last year - with almost a third sent to the US.
Of those issued to the States, 85 related to child pornography, with 69 in connection with sex offences and 7 relating to murder.
Retired detective inspector, Pat Marry, says Mutual Legal Assistance legislation is very useful.
In 2020, 161 European Arrest Warrants were issued for suspects who had fled to another European country.
That's nearly twice as many as the 86 the previous year."