There are several possibilities in Michif to relativize clauses.
The most frequent one is the use of a verb in the so-called conjunct order, used mostly in subordinate clauses and after a focused constituent. The conjunct prefix kaa- is the most frequent, and it relates most often to a nominal, whereas ee- or aen- relates more to the whole clause, and chi- has a future reference.
In short, the vast majority of relative clauses do not contain a particle or pronoun, but a verbal prefix. The verb is always inflected for subject and, in transitive clauses, object.
In addition, a French relativizer particle ki can be used, but that is limited to relative clauses containing French verbs. This includes the copula that will have different forms for person (ki li SG, ki suun PL) and tense (ki litee PST) but not for gender.
These constructions are marginal, and the fact that all of them are subject relative clauses may very well be an accidental gap in the data.
In constructions with a copula in the relative clause, the copula may superficially look like a resumptive pronoun, but these morphemes are better interpreted as strictly verbal.
Source: Laverdure and Allard 1983: 137
Source: Fleury 2007
Source: Bakker 2003
Source: Fleury 2007
Source: Laverdure and Allard 1983: 145
Source: Laverdure and Allard 1983: 104
Source: Laverdure and Allard 1983: 106