Nineteen-year-old Abdulrahman El Bahnasawy's parents asked Edney, who represented Khadr, a former Guantanamo Bay prisoner, to look at the case, CTV's Glen McGregor reported Tuesday.
The complaints unsealed Friday did not name the New York City venues.
Charges against a US citizen based in Pakistan, and two co-conspirators were unsealed in a USA court October 6, accusing the three of plotting attacks in 2016 in support of the so-called Islamic State of Iraq and al-Sham (ISIS), on New York City.
Federal authorities announced on Friday three men who planned to detonate explosives in Times Square, #New York City subways, and to possibly open fire in a concert hall during the holy month of Ramadan in June 2016 were arrested.
In an April 2016 communication, Abdulrahman El Bahnasawy, one of the potential terrorists, said to an undercover Federal Bureau of Investigation agent pretending to be a fellow #ISIS supporter, "We [the men] will show them what they hadn't seen in 2001".
The would-be terrorist who admitted to plotting with two other men to attack concerts, subways and Times Square has a history of mental health issues and drug use, according to documents unsealed on Monday.
A Canadian teen who pleaded guilty to terrorism-related charges in connection with a plot to attack New York City landmarks has met in prison with Alberta lawyer Dennis Edney, who previously defended Omar Khadr, CTV News has learned. Prosecutors hope to extradite these men to America.
Trump threatens broadcaster NBC after nuclear report
It's unclear how Trump's suggestion would work, as only television stations are subject to FCC licensing, not the networks. Officials reportedly were surprised by Trump's suggestion, but said no expansion in the nuclear arsenal was planned.
In New York, which hosts Times Square New Year's Eve and other events surrounded by high-rises, police say they use rooftop snipers to scan for threats, and make security sweeps of nearby hotels.
The investigation involved an FBI undercover agent posing as an Islamic extremist and communicated with El Bahnasawy by smartphone, according to criminal complaints.
Newly released letters from defence lawyers and a NY prosecutor, filed with a US court, show El Bahnasawy suffered from drug addiction and mental health issues.
Around the same time, the two allegedly had been talking with Salic, known as "the doctor", about getting money to carry out the attack.
The undercover also sent Salic a picture of hydrogen peroxide El Bahnasawy had bought to carry out the attacks; Salic allegedly responded by saying he might carry out his own attack if he wasn't able to go to Syria to join ISIS. He told the undercover agent his ultimate goal was to join the Islamic State group in Syria but that "it would be a great pleasure if we can slaughter" people in NY, the papers said.
All three suspects are facing a variety of charges carrying life terms in prison, including conspiracy to use weapons of mass destruction, conspiracy to bomb places of public use and public transportation, and conspiracy to commit acts of terrorism transcending national boundaries.
Haroon was arrested in Pakistan in or about September 2016, and SALIC was arrested in the Philippines in or about April 2017. They're awaiting extradition to the United States, and it's unclear if they have attorneys.