A file called "nunu" had more than 11,000 objectionable files a jury trial heard as it began in the Dunedin District Court yesterday.
He is charged with three representative charges of just possession that are only relevant if the jury does not find him guilty on the main charges.
Counsel Brendon Stephenson said it was not disputed Buckley owned the online account the files were found on, but that he did not know they were objectionable.
Crown prosecutor Richard Smith started his opening statement by reading the undisputed facts of the case.
In 2019, the Department of Internal Affairs was made aware of two public links circulating online containing files that showed the sexual exploitation of children or young people, from teenagers to babies.
An investigation by the department, with the help of Mega Ltd whose website contained the files, showed 310 users in New Zealand had accessed the folder.
One of those users was the defendant, the jury heard.
Mega gives its users "secure cloud storage", senior inspector of publications at the department John Peacock said when giving evidence yesterday.
It "allows a user to save their computer files in a location other than their device".
It was found that on four separate occasions over June 8, 12, and 19, 2018, Buckley viewed the link and saved the files to his cloud storage on Mega.
Buckley created his account on the first day he viewed the videos.
Mr Smith said a user did not have to save the files to view them; they appeared as a "mosaic thumbnail" once a user opened the folder, showing snapshots of videos or images.
"It was readily apparent what the nature of the material was," Mr Smith said.
Mr Peacock said if you just viewed or played the video, Mega would not record that. Activity was only recorded if a user imported or downloaded the files.
Buckley could have opened the material, realised what it was and clicked away but he deliberately saved the files, then deleted them four times, the court heard. Mr Smith said he "took it one step further".
To prove he had possession of the material, the Crown had to show that Buckley had the material in his account, he knew what they were, that he intended to control them and voluntarily had them.
"No-one in this room is going to dispute the horrendous disgusting nature of child sexual material," Mr Stephenson said.
The jury in front of Judge Michael Turner and a jury of six women and six men continues.
