Most of them were caused by section 44 of the constitution. Some, like Fraser Anning, Andrew Bartlett, Peter Georgiou and Jordan Steele-John are already sitting in the chamber. Some more, like Kristina Keneally and Richard Colbeck, are still working their way through the system and will arrive in Canberra soon. George Brandis will also shortly be replaced.

This frenetic turnover undoubtedly has some upside, as many of the newcomers bring real quality and varied experience. But it also has a serious downside. The new senators' personal characteristics and the potential change in the balance between supporters and opponents of the government are only part of the story. The rise and fall of political parties in the Senate is another consequence, as is increased inexperience in the chamber.

But the two main issues are the way in which the connection between voters and those senators they chose directly at the last federal election has been broken, and what the replacements reveal about the internal factional processes that are business as usual for political parties.

These matters are specific to the Senate, as there is more transparency to House of Representatives processes. First, public by-elections are held for the House when MPs need to be replaced and, second, preselection processes are more transparent at the local electorate level than they are at the state-wide Senate level. Just who ends up in the Senate often emerges from a black box known as internal party politics.

Gichuhi and Molan are examples. Gichuhi, the Kenyan-born senator from South Australia whom Malcolm Turnbull warmly welcomed, and Molan, the outspoken former army major-general from NSW, have arrived by circuitous routes.

Gichuhi replaces Bob Day, the Family First senator, and entered the Senate in April 19 last year after Day was ruled to have contravened section 44 through his business dealings with the government. She was the next Family First candidate at the election and so was next in line.

Almost simultaneously, the Family First Party was taken over by Cory Bernardi's Australian Conservatives Party, but Gichuhi declined to join that party and sat as an independent from May 2017, after just two weeks as a Family First senator. She announced recently she had joined the Liberals, restoring in a round-about way the SA seat the Liberals lost when Bernardi defected.

But all this happened without anyone asking SA voters what they thought. They are the losers. Gichuhi has acted like a free agent since she was overtaken by events beyond her control.

Molan replaces the Nationals' Fiona Nash, formerly a minister and deputy party leader. In NSW, the Liberals and Nationals run a joint ticket, but that is not taken into account by electoral law so the Nationals effectively lost that seat to the next candidate on the joint ticket. She happened to be a Liberal, Hollie Hughes, who was also ruled out by the High Court for having taken an office of profit under the Crown since the election, a patronage position as a member of the Administrative Appeals Tribunal.

Next in line was Molan, who comes not just from a different party from Nash but from a different Liberal faction from Hughes, such is the lottery of the NSW Liberal-National ticket, which is the product not just of inter-party but inter-factional negotiation. All of that has been overturned and it is Nationals' voters in NSW who have lost out.

Other cases illustrate the same general points. Among the smaller parties, Malcolm Roberts' replacement, Fraser Anning, left One Nation after a record short period to sit as an independent. One Nation voters lose out. The departing Greens' senators have been replaced by those next in line on their respective party tickets, but it still means that new senators emerge who are scarcely known to voters.

Among the larger parties, the factional nature of Senate tickets and replacements is emphasised. The speculation about who would replace Sam Dastyari centred on the NSW Labor's right faction because that is where the decision was made. It was Keneally, the former NSW premier, who got the nod over her NSW right competitors.

In the Queensland LNP, factional infighting between moderates and conservatives has already begun as Brandis' replacement is discussed within the party.

An unintended consequence of the rash of Senate replacements is the light thrown on both the constitutional provisions for mid-term senate appointments and how political parties work.

It is hard to see how the system can be changed, but it magnifies the disconnect between voters and the electoral process, and throws light on the process by which party tickets are assembled. The minor parties are fragile entities and subject to a lot of infighting and coming and going between elections, as developments in One Nation, Family First and the Nick Xenophon Team showed recently. The major parties are more stable but often subject to bitter left-right factional infighting behind closed doors.

Democracy is strained to breaking point by all these goings on, which contribute to the declining trust in and respect for government, which has now become dangerously pervasive.

John Warhurst is an emeritus professor of political science at the Australian National University.