Lawsuit
Litigation
noun, verbal noun, の adjective
If you sue and bring about a lawsuit, you are bringing about a lawsuit.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
その訴訟に関する書類は、弁護士によって全てきちんとファイルされている。
The documents related to the lawsuit have all been properly filed by the lawyer.