Mass Effect has a colorful bunch of main characters throughout its trilogy. It is truly a ragtag team that are bonded by one goal but have many different values. Bioware, the creators of Mass Effect, has some of their games take inspiration from Dungeons and Dragons. Perhaps that inspiration is key part of the key to their diverse cast of characters.
Whatever the case may be, Dungeons and Dragons does actually have an alignment chart players choose for their characters that help determine their ways of thinking and actions. These alignments include various combination of Lawful, Evil, Neutral, Chaotic, and Good. Where do the Mass Effect characters fit in such alignments?
10 Garrus: Chaotic Good
Garrus quits his job as a basic Citadel cop because he felt the rules constricted him too much. So despite his background as a cop, he actually does not really fit the lawful alignment. Like many chaotic good characters, he believes rules have to be broken in order to catch the bad guys.
He becomes the maximum example of a chaotic good character when he is introduced in the second game as a vigilante. Though he is a troublemaker, he is certainly not evil. Garrus is never afraid to get his hands dirty to help the little guys.
9 Liara: Neutral Good In 1st Game, Chaotic Good In 2 & 3
Liara goes through major changes throughout the series. She is a curious scientist when introduced in the first game, and is neither lawful or chaotic. She is, however, a good person who empathizes deeply with others.
In the next two games, though, Liara becomes a little more jaded. She both overthrows and takes over the role of Shadow Broker, which makes it hard to remain neutral good. She becomes more of a force of chaos, like Garrus.
8 Wrex: Chaotic Neutral
Do not be deceived by Wrex's brutality, he is not evil. He is simply a Krogan mercenary who kills for money. He does not have an agenda until he decides to focus more on helping his people. Even in helping his own people though, he neither is lawful, good, or evil. He is whatever he needs to be in the moment for the Krogan to thrive, and that is absolutely chaotic.
In terms of leanings, he is arguably more good than evil. However, it is not hard to imagine that he could end up being evil if pushed by certain events.
7 Kaiden & Ashley: Lawful Good
The Alliance military loves their lawful goods. They are the sort who focus on orders but care about what they do at the same time. The personalities of Ashley and Kaiden are perfect examples
Kaiden is undeniably lawful good. Despite his L2 implants which has made others protest and rebel against society, he sticks to the law and tries to do good. Ashley is more of a complicated individual, as shown when she can kill Wrex in the first game without an order. At the end of the day though, she is willing to sacrifice herself just like Kaiden in the first game, to help defeat Saren and save lives.
6 Jack: Chaotic Neutral In 2nd Game, Chaotic Good In 3
Jack looks out for herself most of all in Mass Effect 2. It is hard for someone to be good when they have been kicked down and betrayed all their life. In the third title, though, Jack goes through a lot of positive change. She undertakes a teaching role, in which she clearly cares about her students and wants to be a good role model for them.
Thus, her alignment does have a slight change. She is however, always chaotic. Jack is happy to break rules, as the law never ever helped her in her life. She also does not believe the law will have the best in mind for her students.
5 Tali: Lawful Good
Tali is a good person whose behavior is often guided by the traditions customs and laws of her people, the Quarians. If Shepherd is not super paragon or renegade during her loyalty mission in the second game, she accepts exile instead of risking her father's name being dragged through the mud.
Accepting that exile if as lawful good as one can get. Tali consistently respects tradition and authority, even if it can do herself an injustice.
4 Miranda: True Neutral
Good people do not often join Cerberus, and Miranda is an example of that. However, she is also not strictly evil. She cares most about herself and her sister. She is far from lawful; after all, she joined Cerberus because it organization does not obey the laws. However, she is not chaotic either. She finds chaotic characters, like Jack, too dangerous and impractical.
This is how Miranda acts in the third game as well. While Reapers are killing galactic life, she is still doing her best to look out for herself and her sister.
3 Samara: Lawful Neutral
Samara is incredibly lawful, following the strict justicar code to the point where she can kill one of her own daughters or feels that she has to kill herself. She follows her code as though it is a force of nature she cannot control, rather than a choice.
Her lawful alignment even prevents her from being a fully romance-able companion. She shows an attraction to Shepard if Shepard flirts enough with her, but refuses to go much further due to her code. She is neither good nor evil, because she is lawful to the core to whatever the code dictates.
2 Kasumi: Chaotic Neutral
Thieves are natural chaotic neutral in most stories, and the same goes for Kasumi. She is sometimes good, but she is also sometimes selfish. She is certainly not lawful either, as she is always doing crime.
Her chaotic alignment is natural with her job. She hacks, steals, and admits to even having kleptomania. While she leans towards more good than evil, she is ultimately neutral because she is not exactly space Robin Hood.
1 Mordin: Chaotic Good
Mordin is a doctor who is not afraid to kill people without a second thought. He believes part of helping people is killing people who hurt others. Such a mindset is not lawful at all, especially for a doctor.
He acts on what he feels is right, utterly unburdened by law. The one time he does get upset about ethics being violated is upon seeing his student's genophage cure. In this case, he's more upset that innocents were harmed and killed in the process rather than the fact that rules were broken.