You are asking three distinct questions here.
1. Can a USC spouse petition for his or her foreign spouse?
2. Can it be done inside the USA if the spouse is already in the USA?
3. Would the fact she had been spending more time in the USA than she does outside the USA anyhow affect her successful bid to become a legal Permanent resident in the USA.
Answers:
1. Can a USC spouse petition for his or her foreign spouse?
A USC can petition for his or her alien spouse unless the US citizen petitioner had been convicted of an offense recognized as a sexual abuse of a minor. In such a case, the US citizen spouse would need to ask for a waiver in order to file the petition. The USCIS form to be used is I-130.
2. Can it be done inside the USA if the spouse is already in the USA?
Yes it is possible if the last entry into the USA was based on a lawful admission after inspection or parole under INA 212(d)(5). The process is called adjustment of status and is applied for on USCIS form I 485.
3. Would the fact she had been spending more time in the USA than she does outside the USA anyhow affect her successful bid to become a legal Permanent resident in the USA.
It could since the inquiry is going to be made whether she misrepresented her intentions as to the purpose of her travel to the USA at any time including during any inspection by the CBP or visa application at the consulate.
Answered on Feb 08th, 2018 at 10:27 AM