There'll be some sighs of relief in Canberra and groans from within security agencies after Labor MP Anthony Byrne was prevailed on to reverse his decision to leave the parliamentary Joint Committee on Intelligence and Security.

Byrne was Labor's deputy chair on the crucial committee and its most experienced member, but had decided to move on, having grown frustrated with unsuccessfully pushing for reform of the way Parliament oversees intelligence and security agencies and issues. Earlier this week, right-wing Victorian Liberal MP Michael Sukkar was revealed as the new chair of the committee, in the wake of Andrew Nikolic's defeat in the election; Sukkar has only been in Parliament since 2013, has no security or intelligence background and little committee experience, making it more likely the committee would be given the runaround by agencies and bureaucrats.