Continuing on Michael's observation on the literary structure of Judges, there are other literary techniques involved in the book as well. For example, as others have noted, the choice of judges is almost continually ironic. With few exceptions, those who rise to judgeship are unusual, or display eccentricities that normally would not characterize those in leadership in the ancient Near East:
Ehud: Left-handed
Shamgar: Fights with an ox goad!
Deborah and Jael: Female
Gideon: timid youngest son of small clan
Jephthah: son of a harlot
Samson: a Nazirite, a womanizer, and none too bright.
This can hardly be an accident; sacred author seems to delight in telling us about the unusual judges. It seems to reflect the author's view that this was a chaotic period in Israel's history in which down was up and up was down. Whenever I read it, I think of 1 Corinthians 1:26-31.
