The electoral system
Armenia's experience of democracy before Soviet rule shortly after World War 1 was very much limited, and as a result it was in a similar place to much of post-Soviet Central Asia after the fall of the Soviet Union in 1990: left with the difficult business of building from scratch a system of democratic and constitutional government.
Many post-Soviet countries, along with various other democratising or reforming nations around that time, introduced mixed-member electoral systems. Armenia's 1995 election law provided for a 190-member legislature, with 150 members elected through a two-round system (though candidates only had to secure 25% of the votes to win in the first round). The remaining forty seats were elected through a closed-list proportional representation system, making a mixed-member majoritarian system with a remarkably low share of party-list seats.
For post-Soviet countries with new and weak political parties, independents were relatively successful in the district tier elections. In Russia's first democratic election (in 1993) independents won 48% of the district vote: similar results were, and still are, in the Ukraine.
In the district tier for Armenia at the 1995 election, independent candidates won 72 of the 150 seats, making them by far the largest party in this tier. The Republic Bloc, a party tied to incumbent President Ter-Petrosyan, won 68 district and 20 list seats, making them the largest party (an Organisation for Co-Operation and Security report stated that the President would have the support of two-thirds of the legislature, implying that many independents were actually allied to the President). No other political party won more than ten seats.
The new electoral system represents what will likely be a complete removal of independent candidacies from Armenian politics. The full document, passed last year, divides Armenia into thirteen electoral districts. Parties must nominate a list in each district, and a national list. When voters vote, they choose a party list, and may also cast a preference vote for a candidate on the district list.
Seats are initially allocated between using the Hare quota and largest remainders, with a threshold of 5% for parties and 7% for alliances of parties. However, after the Electoral Commission determines the seat allocation, if no party receives at least 53 seats (a majority of the 101-member Assembly; such a party would then receive a top-up to give them 54% of the total seats), and no 'stable majority' coalition (a group of parties which has been allocated at least 54% of the seats in this preliminary distribution agreeing on a Prime Minister) can be formed within three days, a second round is held three weeks later between the top two parties or coalitions. A further four seats are allocated to ethnic minorities, and there are quotas for women representation.
In the second round, new parties may join with the parties or coalitions in the top two, though seats won by parties outside the top two in the first round are apparently not altered by the second round results. The party that wins in the second round is allocated 54% of the total number of seats.
For allocation of seats to actual candidates within parties, for each party half of their seats are allocated to the candidates on the national list (which is closed). The remaining seats are allocated between the districts using the Hare quota again (based on the number of votes cast for the party in each district, so if the Republican Party were to get 20% of the vote in Yeravan District, 20% of the Republican Party's district seats would be allocated to candidates in the district). Seats are allocated to the highest polling candidates within districts. The system is similar to that passed in Italy in 2015 (see this article for details) but later ruled unconstitutional.
In this election, the Republican Party appears to have won a majority even without the special provisions. The party won 49% of the vote, equivalent to 54% of the vote amongst those parties that passed the threshold. The normal Hare distribution of the 101 seats would give them 55 seats (near-exact 54% of the Assembly).
The new Constitution
Up until a criticised 2015 referendum, the 'Yes' campaign in which was supported by the Republican Party, Armenia was a semi-presidential country. This means that it had a directly-elected fixed-term President as head of state, as well as a Prime Minister as head of government responsible to the majority of the National Assembly, who both share executive power.
The 2015 referendum, in which the proposal was approved by 66% of the vote, changed the system to one that appears to be parliamentary; where executive power is in the hands of a Prime Minister responsible to the legislature. The President is elected by the majority of the National Assembly, but it is explicitly stated that "The Government (the Prime Minister and Cabinet) shall be the highest body of the executive power".
Few discretionary powers are granted to the President, who is not even vested with the power to appoint the Prime Minister; instead, he is expected to appoint the candidate who has the support of the aforementioned guaranteed parliamentary majority. He cannot veto legislation, and the determination of policy is reserved to the Prime Minister and Cabinet.
The question of whether this will increase the power of the Republican Party, and its leader (incumbent president Serzh Sargsyan) is a most interesting one. For Mr Sargysyan, at least, the change will allow him to remain in control of executive power beyond the two-term limit proscribed for the presidency under the previous semi-presidential system.
In a more general sense, if the party system of a country is fragmented, parliamentary governments can be dependent upon shifting coalitions (for example, the Presidency of Nauru) and the parties supporting them can hold only a minority of the legislature, reducing their ability to pass legislation. When a great deal of Armenia's parliament was comprised of independents, a parliamentary government would have been weak, and the fixed-term and non-removable status of the Presidency can give the executive strength through stability.
On the other hand, under a presidential system, the possibility exists that the Presidency and legislature can be in different partisan hands, thus depriving the President of the power to pass legislation. A Prime Minister must at least have the tolerance of the legislature in order to stay in office, and the election law in Armenia actually guarantees a party a fairly comfortable parliamentary majority (this is underlined by a constitutional requirement that one party or coalition must end with 54% of the Assembly seats).
A Prime Minister with disciplined control of his majority political party can pass whatever legislation he supports, and also has control of the executive branch. If the Republican Party are able to maintain control over their members, the new electoral system and system of government will substantially increase their power.