Where is git-blame in SourceTree

Select a file, whether in the ‘working copy’ display or in the ‘commit’ display, and do one of three things:

1. option-command-B
2. menu bar :: Actions :: Blame Selected…
3. contextual menu :: Blame Selected…

If the file you want to blame is not in the modified files list, you need to change the view to File Status View (View –> File Status View), then set the Sub menu to “Show All”