"The government passed the new law because it is convenient to raise the workers salaries".
But some connectors as "because of", "due to", "as a result of "
are always followed by a noun phrase or verb+ing
Because of (due to, on account of, owing to) is a connective preposition that relates additional, information to the main clause. Because of is followed by a noun phrase (NP) that expresses the reason (cause) for the effect stated in the main clause. This prepositional phrase, may be placed before the main clause without affecting the meaning. If so, a comma separates the it from the main clause.
CAUSE EFFECT
Because of the gas explosion, several homes burned down.
connector + noun phrase
Because of an exploding gas line, several homes burned down
Due to the free flow of gas, water could not put out the fire.
Due to free-flowing gas,water could not put out the fire.
On account of the age of the pipeline,it broke.
On account of being so old,the pipeline broke.
Owing to the delay in replacing the pipeline,the accident was likely to occur.