Adjectives and Participles as Nouns
In Swedish, you can turn an adjective or a past participle directly into a noun to describe a person or a group of people. This happens in English too (like "the rich" or "the elderly"), but Swedish uses this structure much more frequently, particularly to describe specific individuals.
Singular Individuals
To refer to a specific person based on a characteristic or an action, use the standalone definite article den followed by the adjective.
In police, legal, and formal contexts, you will frequently see the adjective take the masculine -e ending. This is used when referring to a male, but it is also used generically for a perpetrator or victim whose identity is not yet known. Past participles (like misstänkt, suspected) act exactly like adjectives here.
Plural Groups
To talk about an entire group of people sharing a trait, use the plural definite article de followed by the plural form of the adjective, which typically ends in -a.
Note that comparative adjectives, such as äldre (older), already end in -e and simply keep their normal spelling.
Pointing Out Specific Groups
You can also combine these substantivized adjectives with demonstrative pronouns like de här (these) to point out specific groups, using the same plural -a ending.