The lenition of an adjective follows a feminine noun, and the DNTLS DTS rule does not apply for attributive adjectives.
Note, that's only the singular. With the plural, lenition depends on if the word ends in a slender consonant, and doesn't depend on the gender of the word.
- an bhean bhocht - the poor woman
- an bhean dheas - the nice woman
- an fear bocht - the poor man
- an fear deas - the nice man
- an nuachtán deas - the nice newspaper
- na nuachtáin dheasa - the nice newspapers