It's on the tip of my tongue.
I think there's a word (possibly ending in -ate) which means, loosely, "to make excuses".
Not in the sense found here of "decline", but meaning to try and justify something. It doesn't necessarily have to have the connotation that these excuses are bad ones, or that the action was in fact unjustified, but it could do.
For example, "I accused him of not delivering, but rather than apologise he X"