Can employers refuse employment to any people who have been convicted of an indictable offence?

Laws about employment discrimination vary somewhat by nation. In the u.s., employers must not base decisions on race, religion, gender or national origin or (sometimes) age. Other forms of discrimination are not prohibitied. There are some state laws that add to that list, adding such thing as sexual orientation, but no state in the u.s. provides that an employer may not consider an applicant's criminal history. If it can be considered it can also be disqualifying.