For a person who has committed suicide no Shraddha should be performed.
Manu Smriti 5.89. Libations of water shall not be offered to those who
(neglect the prescribed rites and may be said to) have been born in
vain, to those born in consequence of an illegal mixture of the
castes, to those who are ascetics (of heretical sects), and to those
who have committed suicide,
Similar opinion is stated in Vashishta Dharma Sutras 23.14:
A man who commits suicide becomes a heinous sinner ; relatives of his belonging to the same ancestry desist from performing funeral
rites for him. A person who kills himself by means of a club, water,
a clod of earth, a stone, a weapon, poison, or a rope, is a suicide.
Now, they also quote:
If out of love a twice-born man performs the funeral rites for someone who has committed suicide, he should perform a lunar penance
accompanied by a hot-arduous penance
(For the time being it's only a partial answer as cases of accidental deaths are not covered.)