It comes after the broadcast regulator dismissed previous complaints by Mr Salmond.
The party has lodged a complaint through its solicitors about the different criteria to debates and coverage being applied by BBC Wales where the Abolish the Welsh Assembly Party were given full participation in their discussion programme.
The regulator has previously dismissed complaints from Mr Salmond about a "virtual blackout" of his party by the public broadcaster.
Alba's legal letter states that counsel's advice is that the committee’s decision is "in error and susceptible to judicial review".
The Alba Party chief previously said that while not being included in televised Leaders’ Debates is “deplorable”, the lack of coverage has been “even worse”.