The Senate has voted to establish an inquiry that will investigate the deal between the Western Australian government and the Commonwealth regarding the Bell Act, and the involvement of Attorney-General George Brandis and former Treasurer Joe Hockey.

"This motion passed today compels Senator Brandis and Senator Mathias Cormann to appear before the inquiry to answer questions about their involvement in this deal," Greens Justice spokesperson Senator Nick McKim said.

"The Greens believe that former Treasurer Joe Hockey should also be called to give evidence."

The Greens will tomorrow move to refer matters associated with the Bell Group Companies Act (WA) to the Senate Legal and Constitutional Affairs Committee.

"The allegation that Senator Brandis instructed the Solicitor General to effectively run dead in the High Court are the most serious he has faced in a career that is strewn with misconduct," Greens Justice spokesperson Senator Nick McKim said.

"We need to get Senator Brandis out of witness protection and into an inquiry where he can be questioned about these extraordinary allegations."

If reports of George Brandis instructing the former Solicitor-General to act in a political way and ignore the rule of law are true, he should immediately resign or be sacked as Attorney-General.

"It appears Senator Brandis was trying to interfere with the Solicitor-General to stitch up a politically cosy deal for the Western Australian Liberal Government," Australian Greens Justice spokesperson Senator Nick McKim said.

"If it looks like corruption and smells like corruption, then it probably is corruption."