GIVE ONE ENOUGH ROPE AND HE WILL HANG HIMSELF

{informal} Give a bad person enough time and freedom to do as he pleases, and he may make a bad mistake or get into trouble and be caught. - A proverb. * /Johnny is always stealing and hasn't been caught. But give him enough rope and he'll hang himself./ - Often used in a short form, "give one enough rope". * /Mother didn't know who robbed the cookie jar, but she thought she could catch him if she gave him enough rope./