Although filing for legal permanent resident status does not technically invalidate his tourist visa, there is an issue with conflicting intent. With a tourist visa, you are only permitted to stay for short periods and must return to their home country. A big part of that is showing ties to the home country. Filing for permanent resident status undermines that. Because of that, he may not be allowed entry.
Answered on Jul 29th, 2014 at 6:56 PM