The leak of 11 million documents, dating back 40 years, came from an anonymous source who used encrypted digital communications.
The parliamentary bill committee meets on Monday 11 April and the NUJ is calling for substantial amendments to the bill.
The NUJ has organised a public event in parliament with the Law Society and Bar Council on Monday 11 April, at 5pm in committee room 11, as part of the campaign to amend the draft law and introduce legal protections for journalistic sources, materials and activities.
Michelle Stanistreet, NUJ general secretary, said: "The current proposals contained within the investigatory powers bill justify the state surveillance of journalists and represent a significant threat to press freedom in the UK.
"The Panama papers clearly show the importance of protecting journalistic communications and sources from state surveillance. We are urgently calling on all politicians to take action and amend the legislation to safeguard press freedom in the UK."
The latest proposals contained within the investigatory powers bill (intended to replace the RIPA powers) include clause 68 as the only reference to journalists in the legislation.
The relevant sections of the bill that impact (directly or indirectly) on journalists include powers to:
1. Obtain journalistic communications data
2. Intercept journalistic communications
3. Access and examine citizen’s bulk data
4. Interfere with equipment (this includes hacking computers to gain access to passwords, documents, emails, diaries, contacts, pictures, chat logs and location records and/or turn on microphones or webcams and/or alter or delete items).
According to the NUJ, Clause 68 provides extremely limited safeguards for the media. These safeguards only apply when the state intends to identify a source in relation to communications data. There is no prior right of notification for the journalist or media organisation, there are no mechanisms to challenge or appeal decisions. These safeguards are inadequate when compared to existing protections for journalists specified in the Police and Criminal Evidence Act 1984 (PACE).
The bill also provides the legal framework for journalistic sources, materials and activity to be deliberately, incidentally, collaterally or accidentally sought or obtained, by the police, intelligence agencies or other public bodies.
If journalists don’t know their work and their sources are being compromised then it becomes practically impossible to protect sources and whistleblowers, says the NUJ.
