Weak or Strong?

I rate my character Day as a strong character.  Why I think this is because Day goes around doing crimes and weak characters wouldn't do that, also Day never gives up, he keeps trying.  I think everyone in my group thinks that Day is a strong character because we have all agreed that Day is a bad person sometimes.  But not to his family.  I think after Day gets out of the situation that he is in right now I think hes going to be that same Day!  Why I think this is because I think many people in the past have tried to change him but didn't work so why would one more person change him?  As a result I believe that Day will still stay a strong character.