Upvote:1
Would she have a one year ban automatically, and how can we find out? Is the solicitor just trying to get her to start using him again?
For that kind of situation, your mother-in-law would have had received a paper saying explicitly that she was banned.
Since she left voluntarily, they might have just gave her a warning which is not stored in the system's database.
In other words, there should not be any problem for getting the proper visa but she might have to give strong proof that she will not remain in the UK after her visa expires. It is like showing she has property in the USA, or matter of affairs she needs to deal in the near future in the USA, or anything that states she would have to go back to the USA.
Just as with any kind of visa, embassies don't want to risk, and might refuse her visa request if they think she will overstay in the UK again.