Pre-Employment Verification Check through Email - Documentation check

Hi, I am trying verifying an Applicant's Previous Employment from XYZ company. I have taken Applicant's consent through email for the background check.
For email verification process, when sending email to XYZ, can I attach the previous employment documents (relevant to XYZ Company - such as experience letter submitted by the applicant) to verify authenticity of the documents? Is it a good practice to ask the Previous employer to verify the documents?
Thanks,
Akshara

Yes, the comments of previous employer can be taken. Presuming that the employee has submitted relieving order/service certificate of previous employer, it is proper and ethical to get it verified by them.