There has been an increase in car accidents caused by the elderly.
この場合、次のような言い方ができますよ。
ーThere has been an increase in car accidents caused by the elderly. Once people get too old, they should be made to return their license.
「高齢者の車の事故が増えている。高齢になったら免許を返納させるべきだ」
There has been an increase in car accidents caused by the elderly. で「高齢者の車の事故が増えている」と言えます。
to return one's license で「免許を返納する」
ご参考まで!