Nick Kaufman, a lawyer for Saadi Gadhafi, told CNN he wants his client freed from U.N. sanctions that prevent him from international travel.
"There has been at least one assassination attempt (on his life)," said Kaufman.
Gadhafi is under protective custody. He's the subject of an Interpol Red Notice issued at Tripoli's request in September. He's wanted for "allegedly misappropriating properties through force and armed intimidation when he headed the Libyan Football Federation."
Gadhafi fled to Niger after his father's regime collapsed last year. Moammar Gadhafi died after falling into rebel hands in October.
The Libyan government wants Gadhafi handed over, though Niger authorities, CNN adds, have raised concerns about the possibility for a fair trial.
Another of Gadhafi's sons, Saif al-Islam Gadhafi, is suspected of committing war crimes during last year's civil war. He's in Libyan custody.
The International Committee of the Red Cross this month met with Libyan leaders to brief them on international laws related to detainees held in connection with last year's civil war.