The word "convict" refers to a person who has been found guilty of committing a crime and has been officially sentenced by a court of law. Full definition
To expand on your first point: it is actually possible / common to take away rights of people convicted of crimes. (politics.stackexchange.com)
If convicted in court of armed robbery, you will certainly face prison time, and the length of the sentence will likely be quite significant. (cochranfirm.com)
With regards to surrounding himself with persons convicted for drugs - related offences, space constraints would limit us to naming only three. (ghanapoliticsonline.com)