They've made a litany of claims and some are more absurd than others as they've never provided evidence in their secret kangaroo court.
https://en.wikipedia.org/wiki/Andrew_Brunson
Bottom line he got picked up w/ a ton of other people in 2016 in what amounted to a purge. In years past they've been criticized for their "insulting Turkishness" religious prosecution.
https://en.wikipedia.org/wiki/Freedom_of_religion_in_Turkey#Abuses_of_religious_freedom.
The Christian community is like 0.2% there iirc. While they seem to tolerate their minority Armenian Christians to a degree it's pretty obvious it's a case of American + Christian that checked all the right boxes for them. The guys lived there 23 years and had a congregation of around 25. Never registered on the govts radar till the Turkish version of McCarthyism and paranoia took hold after the failed coup attempt. Now we're supposed to believe this guy was lined up to be CIA chief in Turkey after the coup.
They can call the charges whatever they like but an American Christian is always going to be on their list of "usual suspects".
"insulting Turkishness" was always just a means to punish apostacy. They're not secular in a western sense of the word.
Also a pretty good article on it.
https://www.dw.com/en/andrew-brunson-us-pastor-on-trial-in-turkey-on-terror-charges/a-43400601
What are the charges against Brunson?
Ankara accuses Brunson of gathering intelligence using his religious work as cover, and working to convert Kurds to Christianity to "divide" the country.
He was originally charged with membership of Gulen's group and risked life imprisonment.
The latest indictment explicitly states he is not charged with being a member of Gulen's group or the PKK.
Literally charged w/ trying to convert kurds to Christianity to "divide the country" . They dropped all the gulen and pkk nonsense
@Boukert - Just letting you know I updated this comment w/ more info.
As far as i know it isnt "spreading christianity" that is counted as terrorism. It's the alleged ties of the pastor with Gulen, for now Turkey is still a secular state.... for now...