Learn Finnish: Tarkistakaa, onko toimikunnalla toimivalta tutkia. - Check if the committee has the authority to investigate.

It acts as a complement to the abstract noun toimivalta (authority). In Finnish, many abstract nouns that express a right, power, necessity, or opportunity (such as valta, oikeus, aika, or mahdollisuus) directly govern a 1st infinitive. Just like in English "authority to investigate", Finnish uses the basic dictionary form: toimivalta tutkia.

How does onko translate to "if" or "whether" in this sentence?

To form an indirect yes/no question like "Check if...", Finnish doesn't use a separate word for "if" (like jos, which is only for conditional "if/then" statements). Instead, you add the question clitic -ko/-kö to the verb and move it to the front of the clause. Since the base statement is toimikunnalla on (the committee has), the indirect question becomes onko toimikunnalla (whether the committee has).

Since toimivalta is an abstract concept, why isn't it in the partitive case (toimivaltaa)?

In a "have" construction (-lla on), the thing possessed is grammatically the subject. While uncountable or abstract nouns often take the partitive when they are subjects, toimivalta in this legal/administrative context is treated as a single, complete entity (a specific mandate or jurisdiction) rather than an unmeasurable mass. Therefore, it stays in the nominative case.

What is the exact meaning of toimivalta, and how does it differ from just ?