"Inmate's income. Amounts
received for work performed while an inmate in a penal institution
aren't earned income for the earned income credit. This includes amounts
received for work performed while in a work release program or while in
a halfway house. If you received any amount for work done while an
inmate in a penal institution and that amount is included in the total
on line 7 (Form 1040 or Form 1040A) or line 1 (Form 1040EZ), put "PRI"
and the amount on the dotted line next to line 7 (Form 1040), in the
space to the left of the entry space for line 7 (Form 1040A), or in the
space to the left of line 1 (Form 1040EZ). "