Do we have a commit prior to the buggy commit

I understand we can get the buggy and fixed commit by using '-b' and '-f' options but I am looking for pre buggy commit so that I know if the test case was added newly or it was modified before it failed

defects4j checkout -p Lang -v 1b -w /tmp/lang_1_buggy
defects4j checkout -p Lang -v 1f  -w /tmp/lang_1_fixed

Is there an option to get the original commit prior to buggy commit ??
 