He escaped from a New Jersey prison in 1970 and hijacked a US airliner two years later while dressed as a priest.
His lawyer says Wright, 68, should serve any prison time in Portugal, where he is now a citizen and where his wife and two grown children live.
The FBI tracked him down last month not far from the capital, Lisbon.
'Very afraid'"I have no doubt that if he goes back [to the US] he will die. He is very afraid," Wright's lawyer, Manuel Luis Ferreira, told Reuters news agency, adding that his client was in poor health.
"He believes they think that he tried to humiliate them, that they'll make an example out of him... he believes that he will be killed in prison."
The judge will ask the US to submit its counter-arguments and may call witnesses to testify before ruling on the convicted killer's case.
The US wants him extradited to serve the remainder of his 15- to 30-year sentence for the 1962 murder of a petrol station owner in New Jersey.
Wright became a Portuguese citizen, taking another nameWright served seven years in prison before breaking out with three other inmates.
Then aged 29, and as part of the militant Black Liberation Army group, he hijacked a US plane to Algeria in 1972, the FBI says.
Wright is said to have produced a gun from a hollowed-out Bible and held it to a flight attendant's head.
At Miami airport, he and his accomplices demanded a $1m ransom.
The passengers were freed after the money was delivered by FBI agents forced to wear only swimsuits so the gang could see they were unarmed.
While the other hijackers were later caught, Wright remained at large for more than four decades - until his arrest in rural Portugal last month.
In 1991, after marrying a Portuguese woman, Wright became a Portuguese citizen and took the name Jose Luis Jorge dos Santos.
This new identity was given to him by Guinea-Bissau, a former Portuguese colony in West Africa, but was recognised by Portugal when Wright was granted political asylum there in the 1980s.